Swapping Apple IDs

I have two Apple IDs A (xxxx@mac.com) and B (yyyy@foo.com). The first I use for iCloud the second i use for subscriptions and media purchases. (Yes, this is a legacy of the old Mac/iTunes account nonsense.)

What I want to do is associate the email address xxxx@mac.com with Apple ID B and (eventually) delete Apple ID A. There are no purchases associated with Apple ID A, so I won’t lose access to anything. All of my purchases are associated with Apple ID B.

Can I do this?

1. Set the email of Apple ID A to placeholder@foo.com (i have access to this email account)
2. Set the email of Apple ID B to xxxx@mac.com
3. Use Apple ID B for iCloud functions with email address xxxx@mac.com
4. Delete Apple ID A

I cannot see any reason why I can’t do this, but I wonder of anyone else has ever tried to do this.

Diane