How to best handle repo transfer?

I have a gh-pages hosted repo with a custom domain configured already as an apex domain pointing to github’s servers: https://billimek.com/billimek-charts/

I’m trying to figure out the best approach to take in order to transfer the repo to a different organization. I know that github will properly redirect the old repo URL to the new organization/repo URL, but the custom github pages URL doesn’t redirect.

I want to transfer the repo in a way that is least disruptive to folks using the custom github pages URL and wonder if the following will work?

  1. de-couple the domain’s A record from github
  2. establish an external self-hosted site that will properly redirect users to the gh-pages hosted site
  3. transfer the repo
  4. alter the self-hosted site to redirect users from the old domain to the ‘new’ transfered gh-pages hosted site

If that’s not a good idea, the only other approach I can think of is to establish a net-new repo, copy all of the data, and update the old repo telling folks about the new home. I’d like to avoid this approach if possible though.

Has anyone encountered a similar situation and have any tips?