It actually has for a bit now going back to 5.4.5 for the Trio’s supposedly.
References:
https://documents.polycom.com/bundle/ucs-sfb-dg-5-8/page/c2503958.html
I spoke with Polycom the other week too to confirm this and they claim it does work as well. Whether anyone outside of Polycom has gotten it to work though is the question 