The cost in IC days to upgrade twice obsolete units is incredibly cheap. By twice obsolete, I mean upgrading level 1 to level 2 after you have researched level 3. By cheap I mean that it can cost less than 7% of the cost of building a new unit to upgrade one twice obsolete level. Or to look at it another way, it costs less than 1/4 of the expected upgrade cost that you would normally occur going from level 2 to level 3.
The primary factor for this seems to be an incredible time reduction. I tested this playing Germany with twice obsolete upgrades of interceptors from level 1 to level 2 and of tactical bombers from level 1 to level 2. Both upgrades were held back until after I researched level 3, so this was two levels behind. For the interceptors, it took only 13 full days to get to a 99.13% upgrade level. For the tac bombers, it took only 17 full days to get to 99% completion. Both needed a small fractional finishing day. Germany's displayed upgrading costs were 55% in 1937 after two central planning slider moves for the interceptor upgrade and 60% displayed or 30% actual for the 1938 tac bomber upgrades.
Note that if you proceed with the normal upgrading such as level 2 to level 3 in this example, the upgrade times for the interceptor 2 to 3 upgrade would be 52 full days, yet it took only 13 full days for the level 1 to level 2 upgrade. So your are looking at about 1/4 of the time. Normal upgrades of one level start with a 1/4 time basis, so we have a .25*.25=.0625 or 6.25 time percentage basis for twice obsolete upgrade. The IC per day cost in contrast is only slightly smaller. For the interceptor example, it would be 71% of the cost of building a new level 3 interceptor. Modest IC cost reduction but around a huge 15/16 time reduction for twice obsolete upgrades.
So the cost of upgrading twice obsolete units and brigades is nowhere as bad as it seems. This seems to be a change in 1.3 from previous versions (I tested this with 1.3b). I don't recall anyone noticing this in 1.2 and testing this and posting this on the forum. The overall cost to upgrade twice obsolete units one level may be as low as just 7% of the cost of building a new unit. Or about 1/4 the cost of a normal one level upgrade. Also note that you can not see this anywhere in the game; you need to deduce, test, and observe this to extract the math. The incredibly fast twice obsolete upgrades, however, will be noticeable.
METHODOLOGY: I used a saved January 1937 German game. I disbanded the starting HQ and the eight starting tac bombers which left only the three starting level I interceptors that needed upgrades. I researched the level 3 interceptor in 1936. I waited for midnight to reset the production screen so that the upgrade showed only the three interceptors. The upgrade cost at that point was 25.18 for the three interceptors or 8.39 per air unit. I started the upgrades and noted that the statistics folder page for air wings showed a percentage gain after 1 day of 7.63% After 13 full days it was at 99.13% or an IC days cost near completion of 8.39*13=109.11 IC days. With the last fractional day, the total cost in IC days was about 110.07 You can contrast that with the cost of building a new level 3 interceptor which was 11.7 IC a day for 135 days or 1579.5 IC days. As a percentage, the twice obsolete upgrade cost for upgrading one level was 110.07/1579.5 or just 6.97% of the cost of building a new interceptor. Note that there are some rounding effects which effect these percentages, as would any slider moves which effect upgrading costs.
A CAUTIONARY NOTE about trying to do this twice obsolete upgrade in your games. After upgrading from level 1 to level 2, the upgrading mechanism seems to proceed to upgrade the level 2 units to level 3 rather than switching over to the level 1 units. I noticed this when trying to upgrade eight tactical bombers from level 1 to level 2. With a trial and error method, I had enough IC to fully upgrade 2 at a time, so I prioritized one formation of four. When the first two of the four finished, instead of upgrading the other TAC 1 to TAC 2, it stayed with the upgraded TAC 2 and started to upgrade them to TAC 3. So I had to switch the TAC 2 to a different formation which left the two TAC 1 in the prioritized formation. This will require some micromanagement to get the full benefits of this twice obsolete upgrading.
EXAMPLES OF HOW YOU COULD USE THIS IN A GAME? Besides using this for interceptors and tac bombers for at least one upgrade, you could also use this for any starting light armor I div such as the starting three that Germany has. Wait until you finish research on the improved light armor (light armor 3) before prioritizing just the one formation of light armor I. Then allocate a few IC to upgrades and note in the statistics page how much progress is being made after one day. Make some IC adjustments and find a daily % upgrade increase that seems to be good enough. For one armor div, that might be 5% a day. After getting the upgrades done from light armor I to light armor 2, stop upgrading this formation. Wait for research to be done on the basic medium armor 3 div. Then prioritize that formation and upgrade from light armor 2 to light armor 3. This would allow you to twice take advantage of the much cheaper twice obsolete upgrade cost before you have to pay the normal upgrading costs of going from light armor 3 to armor 3.
You could also do this with Cav units or artillery brigades where you can have more than one obsolete upgrade level. If you already have Cav 4 Semi Motor researched while having Cav 1 div, you could have two rounds (Cav 1 to 2 and Cav 2 to 3) of very cheap twice obsolete upgrades before having to pay the normal one step upgrading costs. With Great War artillery brigades, you could have even more rounds of twice obsolete upgrades.
WOULD THIS TWICE OBSOLETE UPGRADE FACTOR MAKE UPGRADES A NO BRAINER? Probably not, especially for countries with very high upgrade costs such as the Soviet Union which start out with the highest upgrade costs. The SU has full central planning and full drafted army which means a net 125% of displayed upgrade costs which mathematically turn out to cost about 63% of the normal upgrade cost. You can contrast that with the Germany examples above which had a displayed upgrade % of 55% which means a 30% actual upgrade cost in 1937. It would still be very cheap to upgrade the Soviet Cav from level 1 to level 3, but the last upgrade would be near the 63% level depending upon which slider moves were made. Additionally one would have to supply the CAV if they are on the field which costs 1.2 or 1.3 supply a day. Disbanding the cav and building them from scatch at a much later date would probably be a cost saver.
If the Soviet Union player wants to keep infantry on the field rather than using the exploit (trick?) of simply disbanding all of the starting inf div, he could wait until 1939 infantry were researched before trying to prioritize and upgrade the numerous 1918 inf div. At that point, however, even with the first twice obsolete upgrade being very cheap, it might be better to disband the 1918 inf rather than upgrading cheaply once. To fully understand this, one would have to play the SU and see what the combination of slider, minister, and tech effects was and then make a judgment call about whether or not to upgrade the 1918 inf div. It might be useful, however, to upgrade the starting armor div when you could take advantage of the twice obsolete factor as these armor div can be put in a formation with the starting motor inf div to create a combined arms formation with the +15 CA defensive bonus that can be used to quickly support defense threatened provinces.
Thread note: there was some previous discussion of this in another thread:
Should I upgrade or produce new units as the USSR?????. Look for Wolfhead's posting and my preliminary responses to him.
The primary factor for this seems to be an incredible time reduction. I tested this playing Germany with twice obsolete upgrades of interceptors from level 1 to level 2 and of tactical bombers from level 1 to level 2. Both upgrades were held back until after I researched level 3, so this was two levels behind. For the interceptors, it took only 13 full days to get to a 99.13% upgrade level. For the tac bombers, it took only 17 full days to get to 99% completion. Both needed a small fractional finishing day. Germany's displayed upgrading costs were 55% in 1937 after two central planning slider moves for the interceptor upgrade and 60% displayed or 30% actual for the 1938 tac bomber upgrades.
Note that if you proceed with the normal upgrading such as level 2 to level 3 in this example, the upgrade times for the interceptor 2 to 3 upgrade would be 52 full days, yet it took only 13 full days for the level 1 to level 2 upgrade. So your are looking at about 1/4 of the time. Normal upgrades of one level start with a 1/4 time basis, so we have a .25*.25=.0625 or 6.25 time percentage basis for twice obsolete upgrade. The IC per day cost in contrast is only slightly smaller. For the interceptor example, it would be 71% of the cost of building a new level 3 interceptor. Modest IC cost reduction but around a huge 15/16 time reduction for twice obsolete upgrades.
So the cost of upgrading twice obsolete units and brigades is nowhere as bad as it seems. This seems to be a change in 1.3 from previous versions (I tested this with 1.3b). I don't recall anyone noticing this in 1.2 and testing this and posting this on the forum. The overall cost to upgrade twice obsolete units one level may be as low as just 7% of the cost of building a new unit. Or about 1/4 the cost of a normal one level upgrade. Also note that you can not see this anywhere in the game; you need to deduce, test, and observe this to extract the math. The incredibly fast twice obsolete upgrades, however, will be noticeable.
METHODOLOGY: I used a saved January 1937 German game. I disbanded the starting HQ and the eight starting tac bombers which left only the three starting level I interceptors that needed upgrades. I researched the level 3 interceptor in 1936. I waited for midnight to reset the production screen so that the upgrade showed only the three interceptors. The upgrade cost at that point was 25.18 for the three interceptors or 8.39 per air unit. I started the upgrades and noted that the statistics folder page for air wings showed a percentage gain after 1 day of 7.63% After 13 full days it was at 99.13% or an IC days cost near completion of 8.39*13=109.11 IC days. With the last fractional day, the total cost in IC days was about 110.07 You can contrast that with the cost of building a new level 3 interceptor which was 11.7 IC a day for 135 days or 1579.5 IC days. As a percentage, the twice obsolete upgrade cost for upgrading one level was 110.07/1579.5 or just 6.97% of the cost of building a new interceptor. Note that there are some rounding effects which effect these percentages, as would any slider moves which effect upgrading costs.
A CAUTIONARY NOTE about trying to do this twice obsolete upgrade in your games. After upgrading from level 1 to level 2, the upgrading mechanism seems to proceed to upgrade the level 2 units to level 3 rather than switching over to the level 1 units. I noticed this when trying to upgrade eight tactical bombers from level 1 to level 2. With a trial and error method, I had enough IC to fully upgrade 2 at a time, so I prioritized one formation of four. When the first two of the four finished, instead of upgrading the other TAC 1 to TAC 2, it stayed with the upgraded TAC 2 and started to upgrade them to TAC 3. So I had to switch the TAC 2 to a different formation which left the two TAC 1 in the prioritized formation. This will require some micromanagement to get the full benefits of this twice obsolete upgrading.
EXAMPLES OF HOW YOU COULD USE THIS IN A GAME? Besides using this for interceptors and tac bombers for at least one upgrade, you could also use this for any starting light armor I div such as the starting three that Germany has. Wait until you finish research on the improved light armor (light armor 3) before prioritizing just the one formation of light armor I. Then allocate a few IC to upgrades and note in the statistics page how much progress is being made after one day. Make some IC adjustments and find a daily % upgrade increase that seems to be good enough. For one armor div, that might be 5% a day. After getting the upgrades done from light armor I to light armor 2, stop upgrading this formation. Wait for research to be done on the basic medium armor 3 div. Then prioritize that formation and upgrade from light armor 2 to light armor 3. This would allow you to twice take advantage of the much cheaper twice obsolete upgrade cost before you have to pay the normal upgrading costs of going from light armor 3 to armor 3.
You could also do this with Cav units or artillery brigades where you can have more than one obsolete upgrade level. If you already have Cav 4 Semi Motor researched while having Cav 1 div, you could have two rounds (Cav 1 to 2 and Cav 2 to 3) of very cheap twice obsolete upgrades before having to pay the normal one step upgrading costs. With Great War artillery brigades, you could have even more rounds of twice obsolete upgrades.
WOULD THIS TWICE OBSOLETE UPGRADE FACTOR MAKE UPGRADES A NO BRAINER? Probably not, especially for countries with very high upgrade costs such as the Soviet Union which start out with the highest upgrade costs. The SU has full central planning and full drafted army which means a net 125% of displayed upgrade costs which mathematically turn out to cost about 63% of the normal upgrade cost. You can contrast that with the Germany examples above which had a displayed upgrade % of 55% which means a 30% actual upgrade cost in 1937. It would still be very cheap to upgrade the Soviet Cav from level 1 to level 3, but the last upgrade would be near the 63% level depending upon which slider moves were made. Additionally one would have to supply the CAV if they are on the field which costs 1.2 or 1.3 supply a day. Disbanding the cav and building them from scatch at a much later date would probably be a cost saver.
If the Soviet Union player wants to keep infantry on the field rather than using the exploit (trick?) of simply disbanding all of the starting inf div, he could wait until 1939 infantry were researched before trying to prioritize and upgrade the numerous 1918 inf div. At that point, however, even with the first twice obsolete upgrade being very cheap, it might be better to disband the 1918 inf rather than upgrading cheaply once. To fully understand this, one would have to play the SU and see what the combination of slider, minister, and tech effects was and then make a judgment call about whether or not to upgrade the 1918 inf div. It might be useful, however, to upgrade the starting armor div when you could take advantage of the twice obsolete factor as these armor div can be put in a formation with the starting motor inf div to create a combined arms formation with the +15 CA defensive bonus that can be used to quickly support defense threatened provinces.
Thread note: there was some previous discussion of this in another thread:
Should I upgrade or produce new units as the USSR?????. Look for Wolfhead's posting and my preliminary responses to him.
