I know it resets every month.Usually when i level up each month it will stay that rank for the rest of the month no problems.But for some reason this month it resets constantly.As for the decay sometimes it's both.It's like when i logout,it doesn't fully save my game progress.I'll exit out to the main menu sitting on one side of the map and log back in somewhere on the other side.Sometimes with damage to my car that wasn't there before.