adsl migration

Is it possible to cancel a migration from adsl?

I have decided to move over to a LLU package my current provider supplies but am now really unhappy about their customer support and now think that an annul contract with them is not good.
I've rang BT this morning and have been told I can cancel the migration of line and adsl upto the day before, can anyone confirm this.

Many thanks

Yes you can cancel them, but the closer you get to the migration date, the more likely that something will go wrong.

Unless there are very good reasons to risk getting stuck with no connection for several weeks, then cancelling a migration should be avoided within about 5 days of it being about to happen