Yamaha Binding support for Party Mode

Hey all,
did anyone find a solution to switch the party mode for a Yamaha AV Receiver (RX-A10xx) on?
The Yamaha Binding 2.2 does not seem to support this feature …
Thx and best regards

I also miss out this feature.
Is the source code available somwhere?
Maybee there is a reason for why this isn’t enabeled?

It seam to be possible in this page: