Almost two months have passed since I moved apartments, and Apple geolocation did not turn out to be an issue at all.
Maybe the trick was to set up correctly the new home address in Apple Maps, and this did trick, in that the iPhone and iPad, who both have GPS and 5G SIM cards in them, could correlate the new location of the same SSID easily, and I never had a geolocation issue with my MacBook Air, which does not have neither a GPS nor a SIM card, and thus must rely on wifi MAC addresses to perform geolocation.
Overall a very smooth transition, including the VDSL service, which kept working at the old location, and started to work automagically at the new location when I connected the same Internet Box 3 to the Swisscom wires at the new location.
Very happy I did not have to struggle on internet connectivity!
Bye, Luca