Do T-mobile Nokia Lumia 521 and 530 fully support UMTS (HSDPA): 850/1900 MHz? So they support all frequency bands for both T-mobile and AT&T?

It seems so from their specifications, but I wanted to confirm.

http://www.gsmarena.com/nokia_lumia_520-5322.php
http://www.gsmarena.com/nokia_lumia_530-6523.php