This email address is not available. Choose a different address.

You cannot change any @icloud.com, @me.com or @mac.com address if listed as the primary email address of your Appleid. You cannot use any third party email address if already in use as an AppleID primary email address, or if used with a deleted AppleID.

Apple hasn’t published any guidance for using an address again. Normally, if your e-mail address was associated with an ID in any way, for example as a Reachable at or Rescue e-mail address, then it can't be reused with another Apple ID for approximately one year. I have also seen posts that stated Apple told them there was a 30 day waiting period before the address could be used again. There have also been posts that if you delete an ID associated with the address, you can never reuse the address. You will need to get another e-mail address to use as your Apple ID or you can try waiting 30 days to see if that works.

I just got off the phone with support and the rep was super helpful. Had my issue fixed in just a few minutes. Had to do with the fact that I apparently never verified my email when I set up my account...

Anyway painless and now I'm all set.