Per The Madden Mobile Community Manager:
Over the past month or so, we've had a number of users banned for suspicious Overdrive scores. I'm not going to get into too much detail here, but after a couple weeks of working with GCs and the team, we were able to isolate why this was happening and unban their accounts.
I realize the silence from me on this issue may have been frustrating but, we had to investigate this thoroughly. Currently, we are installing a fix to prevent this issue from happening further.
I really can't and won't answer questions on this, but you all deserved to know at least this much.