Over 100 wins gone sometimes last night. Cueto was on a streak for me and now he has no stats. I've submitted tickets about this several times now, even on the old game. :(
They automatically will expire after a few days. I've seen 3-7 days usually is how long. If you're in the lead when the game expires, you'll get the win.
Upgrades. Makes quite a difference. I prefer pitching then hitting and finally defense. Do as much of this and also draft picks during player events so maybe you can get an extra player doing stuff you'd already do.
I'm only in need of 250 sacrifices to have them all. I've already thrown about 10 no hitters with 2 being perfect games. Really surprised my pitching has been so good.
I think it has less to do with your device and more about the limitations of both the app software and the server (which routinely times out during other in game actions).