Today T-Mobile has started to push out minor over-the-air updates to a number of Samsung Galaxy devices. Two of them are identical—the S5 and Note are both receiving Chinese language support. The former goes to version G900TUVU1CNK2, while the latter ends up at N910TUVU1ANK4.
The Galaxy Note 3 will get support for Gogo in-flight texting in its update to N900TUVUDNK3. This feature isn't yet coming to the Note 4, but T-Mobile explicitly notes that this feature is on its way to handset in the future. So frequent flyers with last year's Note are all set to go, while those with the current one should be fine eventually.
That about sums things up. If you want to read over the changelogs yourself, you can do so at any of the source links below.