Forum:I have lost all my characters 360

Crap.... all 4 of my characters have gone since I last logged off.

I have been playing Borderlands on my 360 since it came out. I have purchased all the DLC content including the lastest one. I have no mods, modded weapons etc and only played online once and never picked up a gun. I have no pearlescant weapons (never actually seen one) but I have quite a few orange/purple weapons. I have 3 completely legitimate characters at 61 (Roland, Mordaci and Beserker) and I am currently working to bring up Lillith who is at 25 (Playthrough 1) at the moment.

I have recently downloaded purchased DLC4 and ran one mission in playthrough 1 with Mordaci to see if there was any leveling up (there wasn't). Then I fought Knoxx again (as Mordaci) at playthrough 2 to farm the armory once more. After than I decided to wait till the leveling patch comes to play DLC4 as I dont want it to be a walk through. Just now I decided to log back in and play Lillith (still on playthrough 1) soI logged in to my account, started borderlands and this is where my problems began. Once Borderlands started it said that I was not logged in and gave me a blank profile and said nothing would be saved? This is really strange. I shutdown rebooted the xbox and tried again... same thing. I am sure my characters would still be there but maybe there is a bug in the latest update. Anyone else experiencing the same problem? Any ideas?