So just when can T-Mobile customers expect to receive the update? A tweet from the carrier's U.S. support crew, reveals that the update for both models will be pushed out later this year.
T-Mobile customers might not be terribly pleased to learn that while they are waiting for the update, their friends with AT&T are enjoying the fruits of the update, especially Cortana, on the Nokia Lumia 520 and the Nokia Lumia 925. Considering T-Mobile CEO John Legere's feelings about AT&T, the brash executive, and the creepy looking Legere doll, both cannot be that thrilled about this news.
T-Mobile says it will update the Nokia Lumia 521 and Nokia Lumia 925 to Windows Phone 8.1 later this year
source: @T-MobileHelp via WMExperts