Telefónica has completed the migration of its mobile users in Mexico to AT&T’s network and handed back the last of its spectrum to the regulator. In late 2019 Telefónica, which has been reducing its presence in Latin American markets where it is not a leader, announced that its Mexican operating unit, Movistar, had agreed a deal with AT&T to carry 3G and 4G traffic, as well as future 5G. That would enable Movistar to be more competitive with the dominant America Movil, the Spanish group argued, and of course, it will save on the operating costs of running its own network, as well as the heavy spectrum usage fees that are imposed in Mexico. The spectrum that has…