Its just happened like randomly on the app for me, even if I was doing something like training, browsing through teams or even when in the market. Sometimes, I got the message of connection reset, and the game reloaded after, and sometimes no message at all. But, the amount it has happened is far from something expected (happened way too much) and I noticed this happening before even the event started. I cannot use browser platform anymore, but given my past experience, I would expect it to be worst for browsers during the FA period, especially during the FA match of the user's team.
Another thing I noticed is that there were big lags during the recent live matches, and susbstitions came very late. I also noticed that lately, the game slowed down and there were moments of freeze or stops and flashes.