As the event started, I immediately tried to lock in my first PW and get into the game, but I got the dreaded “something went wrong” screen. After several restarts and several hours gone, I still cannot lock in any of my PWs. It’s kinda frustrating as I would have time to play this weekend. 
Had the same issue for the last emrakul event. Sorry to tell you that it lasted the whole event.
Same story in the current event. I check next, when be a same problem, probably fu*** this game.