I'm not at my home machine to check, but I'd start with checking the reward milestone in the milestone set file, then whatever .csv's it's calling. It's possible whatever .csv was called has been changed in 1.8 and it's pulling 25 items from a far more powerful pool than before.
ok so its pulling from item collection faction Aurigan Restoration -
itemCollection_faction_AuriganRestoration,,,
itemCollection_systemStores_Mechs_common_Light,Reference,0,10
itemCollection_systemStores_Mechs_common_Medium,Reference,0,10
itemCollection_systemStores_Mechs_common_Heavy,Reference,0,10
itemCollection_systemStores_Mechs_common_Assault,Reference,0,10
itemCollection_systemStores_MechParts_common_Light,Reference,0,10
itemCollection_systemStores_MechParts_common_Medium,Reference,0,10
itemCollection_systemStores_MechParts_common_Heavy,Reference,0,10
itemCollection_systemStores_MechParts_common_Assault,Reference,0,10
Gear_Mortar_MechMortar,Upgrade,3,1
so....would the way to fix this and keep it the way the author intended would be to just change the ,csv it calls?
and no worries about no being at home i understand the time of year..just if ya get the chance whenever.