We want to emphasise that the items in the list at Update 12 are in that order for a reason. No two-penny web designer, who is willfully ignorant of how email works, knows any better. We have no reason to mislead you. Yes, we want you to move, and yes, we want to help you move, but we don’t want you to do everything in a mad panic that you will regret later. Please keep that in mind.
Particularly be wary of someone who tells you that you have to register another domain. If someone tells you that, run away!
Additionally, unless you are willfully abandoning your saved email on our server, don’t skip step 5 thinking you can do it later!