No, you can change teams between rounds.
That's good news, my team got corrupted somehow, and I had to re-make it, and there may be minor differences as a result, be it nature, or EV's. (Although, I managed to salvage most of it from my log of T-Dos's battle)
Figuring out that Stall will be a larger player in No STAB, I'm gonna have to edit my team a bit. T-Dos didn't run Stall, but, I'm gonna need a few modifications to counteract a full Stall Team, especially something to beat SkarmBliss, seeing as Mixape and Mixmance are both out of the question...
Play Style Predictions for Round 2:
There will be stall still, however, some players may revamp their teams to try and break down stall. As a result, there will be a mix between stall and anti-stall. Should be interesting to see what happens, playstyle wise.
I will be annoyed if I face a Full Stall team. I hate them.