I figured out a SOLUTION to the glitch where randomly your entire online progress would be reduced to level 1. I am going to tell you exactly what happened to me (in explicit detail), and how I avoided the reset. NOTE: this will not help people who already reduced themselves to level 1 and saved.
First of all, I was aware of the glitch when I first started levelling up for the online trophies. I was always worried it would happen to me. Because I'm extremely paranoid, I was always watching for it. Today was the day it occurred. I was already level 30 overall, and with Bane, and level 28 with Joker. The game froze mid-game, so I had to turn off the system (no big deal, it freezes a lot). When I turned it back on and went into online however, I noticed my Arkham Online Rating was 1. WHAT!? I immediately shut the system off in disgust. I went back online and checked again. It said 1, and tried to start saving, so I immediately shut it off. Then I went and sent a scathing email to WB Montreal. Sometime later, I logged back in again, hoping that because it never saved, it wouldn't count. Sure enough, it read 87 for my Arkham Online Rating. YES!
Online it just like offline play. If you shut off before it finishes saving, you're progress won't count. I guess eventually it was able to read my true online progress.
So ALWAYS make sure to look at your level after every disconnect and when you first login. Make SURE it's correct, or shut it off before it saves. I hope this will save someone the heartbreak that I saved myself.