the map should never reset. just keep winning the same one.
teamwork!
but I'm reasonable, so I suggest 2 hours until reset, after a war's won. War won by rooks, you have been awarded perk points. terrain changes in 120 minutes. this is for the guys who took off their lancs or b29's that can't read the map.
maybe it should be 3 hours, since someone might be in the air still. 3 hours + glide time.. lets make it 4 hours.