I was playing match 5 of a league, and after game 1 I started sideboarding. I made the necessary changes to my deck that involved putting multiple cards into my deck and taking an equal amount of cards out, and clicked submit just as the timer was about to run out. The app confirmed that I was ready for the next round, but when I joined game 2 and checked my sideboard it was the same as it had been during game 1. To add on to that, I ended up drawing cards that were in my starting deck but I had meant to sideboard out, so the sideboard screen wasn't glitched. Overall weird interaction this hasn’t happened to me before.