In the process of moving a .co.uk domain over to 1&1 for someone this week, I encountered the undocumented status code of ‘Domain Update Done’.
The domain had previously shown as ‘Ready’ in the control panel and I was able to set the server and mailserver for them using 1&1’s nameserver.
The gotcha is that during the ‘Domain Update Done’ status you can’t swap the nameserver settings. You can still get to change the A and MX records with 1&1’s Nameserver but if you wanted to point it to an external nameserver you’ll have to wait until this status clears.
The official word I got from 1&1 support says : “Domain Update Done status means that a domain is already on its last phase of propagation and normally, this will take 24-48 hours.”
So just be warned that if you want to change your initial settings when transferring a domain, you might get locked out while the domain is being finalised on your account.