Enthusiastic Contrafibularities posted:
Listening in to her phone conversation was straying into the realms of fantasy - the exception being if they already knew her number and were monitoring the phone 24/7. But burner phones by their very nature are purchased with cash along with a pay as you go SIM card, so I doubt they would know anything about it.
I would add, burner phones are predominantly used by drugs dealers for the very reasons I said above. They may be used with one or more SIM cards. Also being cheap, if law enforcement are catching up with them, they don't mind crushing them under foot.