The release of the update was first leaked by French operator SFR to occur last December, which was then delayed. LG Canada later gave a broad ballpark first quarter 2014 schedule. AT&T rolled out its own Android 4.4 update for the G2 last week, but T-Mobile users were left twiddling their thumbs, waiting for their update as well.
A firmware for the LG G2 bearing Android 4.4 leaked out a few days ago, suggesting that an official update is sitting in LG's servers already. Of course, it wasn't official yet, but it gave a glimpse of what could be found in the official update. Most comments noted that the new Android Runtime or ART as well as Tap to Pay NFC system was suspiciously missing from that firmware.
Now LG G2 owners will get to know for real if these changes really made it to the cut. T-Mobile itself isn't saying much in the changelog aside from the Android 4.4 update, some user experience improvements, and a new Auto Brightness feature. No news of the new Knock Code making its way to the G2 either. As expected, the update will be quite big and T-Mobile recommends having at least 147 MB of free storage space on the device. The update will also be delivered only via OTA, so no option for a direct PC or phone download.