Most people using mobile phones make the assumption that if they should change phones SIM’s from a GSM phone, or have their phone number transfered to another phone that the change in the mobile handset may hide them them from anyone detecting the change, but they can be!
There is a little known artifact of communications that’s call RF Profiling. The actual crystal that creates the signal for each mobile is unique so every mobile ever created is really operating at a different frequency within a set tolerance level, and that individual ‘signature’ can be detected, and recorded by the mobile network operator.
Brought to you by YAUPI. (Yet Another Useless Piece of Information)