T-Mobile already announced twice that it will carry the Nokia Lumia 521. The company first unveiled its intentions during Mobile World Congress and then earlier this month said that the phone will be available in May. Now a picture of an internal system from T-Mobile suggests the carrier may have moved that date up a bit.
The screenshot above clearly says T-Mobile representatives should replace the Lumia 820 dummy unit on shelves with the Lumia 521 on the 24th of this month. Carrier launch schedules for phones often change drastically, which is probably why T-Mobile never provided a firm release date in the first place. The phone will be available from Microsoft Retail Store locations, Walmart and T-Mobile retail stores.
The carrier has not yet announced a price although we imagine it will be a lot cheaper than the $99 downpayment required for the HTC One smartphone, which is a lot more powerful.