I'm not banned. I have a TS ms25 drive, which was flashed with Xtreme 5.2A (reporting as ms25) for months. Took the spring update, and played backups on Live since the update (all full stealth discs). Didn't play any backups for at least 24 hours before the bans started. Reverted firmware to stock after hearing about the bans, and have since been happily playing on Live with originals and Arcade games.
One interesting point: my 360 has had R6T3 removed since before I signed up to Live (for downgrading the kernel to the exploitable one). I have no idea how plausible this is, but since people seem to be reporting that they never went on Live with backups and were still banned, the detection of the backup might've been recorded somewhere? If it's an eFuse, then, er, mine obviously wouldn't work
