Sky Max cancellation process

Anyone been through the Sky Max cancel process

* Requesting cancel
* obtaining a MAC code, through the post
* Using MAC code with a normal BT based ISP
* Switch over
* running on new ISP

What I am interested in is do SKY follow the normal Mac process, leaving your line running until the actual change over to the new ISP, or do they cut you off.

What is the experience?

They should not just cut you off, as that would be against the rules. but with an LLU to BT IPStream, there could be some down time, but should not really be more than a day (of course this is dependant on BT)