@GrapheneOS Couldn't some kind of P2P distribution help? The update downloader could be basically a non-seeding Bittorrent client and your servers be seeding clients. At worst case nothing changes for your but this way it is very easy for volunteers to seed it on their own meaning anyone can set up an update mirror without any coordination required.
V
vojta001@gts.vkane.cz
@vojta001@gts.vkane.cz