The developers are introducing big changes to territory wars, in the form of limiting the squads you can use in each war.
So don’t be surprised when you can’t use some of your favorite squads. It’s an odd change given the popularity on the current change. Likely to get people to invest in sub-par characters.
For more info visit this video by mobile game or this one by CubsFanHan. Both are worried territory wars might be ruined.