I’m guessing this is another case of critically important changes to the game that have gone completely unannounced in the game itself?
Can we at least get ingame notifications like “we tarded up more than just the interface! Head to the forums for a list of known screwups!”
Likely because of the defense-variety changes outlined here in the patch notes:
They took effect this week. I agree that in-game announcements are sorely needed, though, for critical changes to gameplay mechanics.
Yes, I also think Devs should make GW defense team slots separate from the Team slots you gain by spending money on VIP. Consuming 6 Team Slots for this GW change seems off-the-mark. I think the first 6 GW DEFENSE Team slots should be FREE to all of us. Also, we need a way to SORT TEAMS so that we can arrange them by OFFENSE / DEFENSE or ATTACK / DEFENSE etc. Way too much scrolling to find teams in the current UI.
It is amazing and surprising how the game evolves to require new features based on the growing capabilities GOW offers! 
NowayJoe2Go