- If your allies have good numbers you can requisite expeditionary forces from them and set invasions yourself, BUT i dont remenber how mechanic work for AI lend troops.
- On bottom right corner there a switch you can turn ON to see allied AI warplans, if theres naval invasion planned you will see it, and try planning your invasion to match they. is very common see many when have uk+usa as allied. but, is very unpredictable when they will launch planned invasions, if you have a decent navy to give naval superiority then chances of AI autolanch will be higher(the most common cause to UK stuck is when they send fleet too far away).