[Ugohcet]

Signal can pull a Durov and start hopping popular cloud hostings and CDNs, pushing latest server IPs via FCM. This worked for a year in Russia - they banned several large subnets of AWS and DigitalOcean, millions of IPs and smaller subnets, temporarily banned Google, but in the end still gave up after a year.

[bubblethink]

Signal has already tried similar approaches (domain fronting), and had to stop because the cloud providers do not want any of it.