I see that Firmware 7.1.3.0991 along with Teams App 1449/184.108.40.2061101205 have been available in the Teams Admin Console for a few days now but there is no mention of these on the Poly site.
Curious when the release notes will be available?
I allowed the TAC to update a couple phones and am still having the phones revert to 'offline' after the update is successful; it takes a factory reset and re-login to bring the phone back 'online' in the TAC.
Our partner Microsoft often receives our firmware prior to Poly releasing this officially. We have not yet decided to release this built. I suggest you work with our Partner Microsoft on any issues around Teams. Microsoft can comment on the changes in Teams App 1449/220.127.116.111101205
I tested this fw on a CCX500 and had to revert to FW 18.104.22.1685 because it has a bug. The phone does not signal a call when someone calls. I tested it on two units and it is the same.