In my current PBEM (playing as CSA), thanks to some luck, FI is about to kick in early 62, before the French have even landed in Mexico.
This is the first time it has happened to me, so I want to be prepared. The way I understand FI mechanism, it unlocks English and French troops on the map, and makes Canada, Mexico, Antilles, and Europe accessible.
My question is, will French Intervention troops, when they land in Mexico (and their Antilles Navy - the Convoi du Mexique) be locked once they appear (since they were not present for the initial unlocking of the forces).
If it so, does it creates an imbalance, since Mexican troops will presumably be unlocked from the beginning of Foreign intervention, free to roam Texas without opposition.