Also, I’m not sure if you’ve seen this already but I’ve been experimenting with a geographically diverse relay using geo DNS to redirect to the closest server with failover if a server fails. It provides some of the benefits of anycast but not all. I’m considering how this could be made less reliant on a single GeoDNS provider. Details of what I have set up are here:
https://www.austrich.net/austrich-relay/