T-Mobile Samsung Galaxy S6 and S6 Edge starts getting a November’s Security Patch. Athough its 1st December 2016, which means you can receive December’s Secuirty Patch in few days.
As this is an OTA update, So if you did not get the Update Notification yet, don’t panic it will reach within a couple of days. In meantime you can check it manually by going through the settings of your device. Moreover, T-Mobile subscribers can also download this update file for the Galaxy S6 and the Galaxy S6 edge from T-Mobile firmware section.