Yeah, I'm not worried about testing HTTP so much -- I've been doing the above. The only shortcoming there is that most of the links are absolute, so every link on his site on my server just takes me to his current server, which means a lot of retyping base URLs to test. But I'm pretty confident in most of the HTTP stuff. Luckily I haven't had to test too many forms or anything.
Ah, hence the drop-down menu in the email account setup that now only offers the .org domain. I've already set up the accounts, and I don't see a way to edit them in cPanel. Luckily, there are only a few, so I can redo those manually. Thanks for that insight -- big help.
Okay, that's good to know for the future, but we're close enough now that I'm not going to sweat it for this operation. We can use my GMail if the client needs to reach me during the final hours.
But I can do this while 3rd party DNS entries are not yet sending the world to our site -- right after I switch the nameservers at the registrar -- so it shouldn't effectively be "downtime" at all.
I just do this via List Accounts > [Username] > Alter Account Settings ? I see that's editable -- for some reason I thought it was not, or I couldn't find it before. This is a relief. Again, thanks.
No need to respond to this message unless it sounds like I'm not getting something.