Users on T-Mobile will be happy to know that an OS update is due to land tomorrow that brings along Wi-Fi calling as well as a few other improvements. Not too long ago T-Mobile began rolling out an OS update to Q10 users and now Z10 owners will be able to join in the fun as well.
A notice in T-Mobile's support docs shows the update will be to OS 10.1.0.4780 and available starting September 5th. This is one of the first times we've seen a carrier drop word of an OS before the actual release but we won't complain about it one bit.
We'll be on the lookout for more tomorrow, but if you're using a Z10 on T-Mobile be sure to keep your eyes peeled and report back if you see the update.