Just to confirm how little I obviously know, this is now working: I thought I had allowed sufficient time for DNS updates but possibly not. In any case please disregard.
I’ve tried to resolve this issue through the documentation but have hit the limit of my knowledge and would be very grateful for any help/advice. I’ve set up a personal website with Jekyll on Github pages and I am trying to point a custom domain to it (www.georgewalkley.com, pointing to georgewalkley.github.io). I am getting the following warning on my settings page (and a similarly-worded build error on commits)
However, the DNS setup for the domain (using 123reg.co.uk) does use a CNAME, as follows:
Thanks for your patience if there is an embarrassingly obvious error in the setup, but any advice would be appreciated.