According to the official specifications for the LG G2x, it appears that T-Mobile will begin to future proof their phones by including radios that operate on both their network and AT&T’s, in anticipation of the merger.
T-Mobile currently operates their 3G and 4G HSPA+ networks on AWS Band IV (1700), but AT&T wants to re-purpose that spectrume for their 4G LTE coverage. AT&T operates their 3G and 4G HSPA+ networks on UMTS bands 850 and 1900, so current T-Mobile handsets would need to be replaced when the network changes are made.
The proposed merger is not expected to close for another 12 months and AT&T says the transition to 4G LTE on AWS spectrum could take several years, so we don’t see this as a big deal for current T-Mobile customers. The day will come when some T-Mobile phones need to be replaced, but AT&T has said in previous transactions they “allowed customers to choose a comparable device at no charge if their device was not compatible with the network.”
We know that AT&T and T-Mobile had been in negotiations for at least three months, so it looks like they decided on letting T-Mobile produce phones that would work on both networks to make the transition process easier.
The T-Mobile G2x is the first phone that supports UMTS bands 1700/2100 for T-Mobile and 850/1900 for AT&T. The global version of the LG Optimus 2X did not support all these bands, so someone at T-Mobile had to request a special radio that could handle both networks.
We don’t know if the UMTS bands for AT&T’s HSPA+ network will be turned on when the G2x hits stores, but a future update to the radio’s firmware could easily enable them when needed.
So if you were thinking about purchasing the T-Mobile G2x and were concerned it might not work in a couple years, you can put your worries to rest because it has the hardware needed to operate on AT&T.