Board Thread:Support Requests - Getting Started/@comment-81.132.181.53-20140202165346/@comment-4712589-20140203102321

2Actimv wrote: When usernames are changing the account is temporary disabled, just wait. If it's still not working after waiting you can use Special:Contact for help.

As an addition. Both accounts are blocked roughly 24 hours to prevent futher editing to both account details, which may prove to be a nuisance during transfer.