You can bring your own AS quite easily at a couple of places such as vultr. I heard TCP works surprisingly well over anycast as routes are more static than one

You can bring your own AS quite easily at a couple of places such as vultr. I heard TCP works surprisingly well over anycast as routes are more static than one would fear. Note that in the case of fly you don't directly get traffic to an anycast IP but through a reverse proxy. I could imagine that they replicate connection states to all pops so that traffic that arrives in the wrong pop can be rerouted.