konfusd:
It's really important that you call the dedicated number
Online chatted with VF, then rang the usual VF Support number: They say there's no dedicated number for the team they referred to as x-squad Team. But a Ninja said he will put it through to my case manager as "opt out" of the migration. It seems I can stay on VDSL for now.
Thanks everyone for sharing your insights on this migration stuff. I wouldn't have known where to start.