Ma Bell reclaims its own

We've lived in this house since 1982. At that time, our telephone company was New England Telephone, a subsidiary of AT&T. New England Telephone became NYNEX became Bell Atlantic became Verizon. Last year, we jettisoned our landline service and just used our cellphones. I was able to transfer our home number, the one we've had since the aforementioned 1982, to my cellphone.
So, why, in the name of little green apples did I receive this note from AT&T, offering us new wireless service because they claimed that we've moved. Are they trying to end the diaspora?