Hello, I know the thread is quite some days old, but running into the same problem: My Shelly 1 devices come up with new MACs after a reconnect which screws up their usage due to IP-pinning via DHCP. Is there any more elegant solution to this available then to install some crazy firmware version ,-) And I also confirm, this has nothing to do with cloud connections, it's just about the local IP.
Regards,
Soeren