I was in the middle of a WAR attack just now. Right after my KS made its way to the center of the base and destroyed the TH, the game decided that I had leveled up and popped the stupid announcement over top of my attack. I was unable to see what was happening until the doggone thing went away. I still 3* but this is bad. PLEASE ensure that this does not happen. I'm playing the game on an android emulator, specifically memu. Not sure if you need any additional information.