I'm already aware of the 1492 vs. 1500 MTU. In any case, that shouldn't cause corruption - only split/fragmented packets
(which can be problematic for secure connnections).
Furthermore, the issue only appeared ~3-1/2 weeks ago. All was fine before and I've hadn't made any changes to my MTU settings.
If you had read the entire thread, you would have read that it appears that Bell fixed the problem at THEIR end.