In regards to the plan, it might be a little optimistic that we will be able to hold off Germany and the other Axis powers with what other forces we have. Maybe ANZAC and Canadian forces gather in Portugal and try to push through that way, while we have a defending force of British/French on the Spanish/French boarder, looking for openings, so that the bulk of their forces can be used to defend against Germany and Italy. It's possible we also have American troops if they are in the Allies when the Axis attack.
Americans cannot join the war before 1941, its in the rules. To be honest, I have previously stated that taking Spain is actually more important than holding France, since if Spain opens another front in the middle of the war, French position is undefensible. If we however, occupy Spain but Grand Baguette collapses, the mountain ranges of Spain will give us a more defensible position, and a smaller front, as well as a fallback position for French troops. This way, we loose territory, but French army, navy and airforce is kept in the war...
My point is, Spain can be France 2.0 temporarily, but if they are ignored it is game over for French troops which will get surrounded and surrendder.
Is there something I am missing ?
i think that there are a few flaws with your plan.
- what if we meet strong enemy opposition and the offence stalls, do we withdrawn or try to smash through.
- what kind of reinforcements should we prepare, armored, motorized or simple infantry?
- will ANZAC forces be fighting under there own command or as a Expeditionary force under UK.
- the armored formation going south, what if they for some reason go to far ahead and get cut off. what will be our plan after a scenario like that.
1-Smash, Spain has a higher priority than France, in my opinion, but that is up to debate. I have elaborated earlier.
2-For Spain, a couple of tank divisions, a few more motorized, and the rest is specialized and normal infantry.
3- ANZAC will keep their own command, since they get their own frontline. However, if they so prefer, New Zealand and Canada can give expeditionary force to Australian generals or the like. (independent ANZAC will be more fun

)
4- This is the thrust that is most realistic to get bogged down, but is it realistic that operation Liberty Prime lasts longer than a month ?(this is how long it is said units can survive without supplies)