Will Samsung S3 phone from MetroPCS stop working in 2015 ?

[Casey Cheung]

My GF just bought a new previous generation Samsung S3 phone from MetroPCS at a pretty good deal for around $300 after rebate discounts with a new activation.

Question:
Will her phone stop working sometime in 2015 after T-Mobile takes over with their GSM network versus the CDMA network from MetroPCS? If so, then what?

Question:
I read an article online somewhere that MetroPCS is offering a new GSM version of the Samsung S3 phone, is this accurate? When I went to a local MetroPCS store yesterday, the rep told me he heard nothing about it.

Thanks,
Casey