Recently everywhere I go IE: Restaurants, shopping malls, I find these 12 digit numbers almost directly proportional to the people around me;. Did an experiment as I never have these numbers at my home. I turned on my Bluetooth and scanned a 4th of July street party get together. I noted roughly 19, 12 digit alpha numeric numbers in my vicinity. They are not Fitbits or vehicles as those electronics have specified identification. Could these be the vaxxed? These numbers seem to only appear on older phones as I've tried scanning on state of the art phones, which do not show these. Chime in if you can infer to better explanation.
Update; apparently it is a Microsoft Identifier aka Bill Gates identifier that is not online yet. No devices are able to connect to these locations.