Hah! More later after I check whether AFS will run offline. Easier said than done.
The question was asked when AFS4 was announced, and the answer then was yes, but only in a very limited area of S-W USA. I have not found a more recent instance.
I switched this machine on and it said the LAN was working but no internet access. So I started the flying machine which said the same, but with great coolness and determination I told AFS4 to start. Steam did its usual check/update thing and the sim came up, with all locations available, working normally. I exited the sim and the machine was still saying no internet, confirmed by the rest of the network.
Even if Steam has its own browser which can take priority, I don't understand how that can work.
I use a wired network. All the bits talk to an 8-port switch connected to mobile broadband hub (= wireless modem/router) which provides the only connection to cyberspace. The wifi access point for the birdie cams connects in the same way.
So at best, all I can definitely say is AFS4 might run offline but probably not
ATB
Mike