> I have also tried building the package in my unstable amd64 virtual > machine with the network disconnected and that build still works, so > this is all a bit strange to me.
Hello. Try building the package using sbuild and the old file backend (as I did) and without disconnecting the network, and the build should fail. Most probably, this means that the package (either directly or indirectly) is trying to access the network, which is forbidden by policy (and RC) no matter what. Thanks.

