Sonos Ace Ultra audio sharing

If you are referring to the Ace Ultra’s new headphone linking feature, you can only have one headphone linking session active at a time.

Known limitations with headphone linking

One active headphone link

Sonos systems allow for multiple sets of Sonos Ace Ultras to complete the headphone link setup process. It is important to note that only a single Sonos Ace Ultra headset may have an active headphone link session at a time. The Sonos App utilizes a BLE control connection to the Sonos Ace Ultra and is not able to utilize multiple BLE connections.

Two Aces have been able to connect to a soundbar via TV Audio Swap for a while now.  I'm sure the same feature will be available for the Ace Ultra.  However, you cannot connect two Ace units to the same device via Bluetooth.

I am not referring to either of these features. Other devices are able to have 2 pairs of headphones linked to same device at same time for watching TV (ie when kids are asleep nearby). It is my understanding that Sonos Ace and Ace Ultra are incapable

I’m not understanding what you want. You can use 2 pairs of Aces or Ace Ultras to listen to your tv, using the TV Audio Swap feature, when kids are asleep nearby.

I'm not sure why you say you aren't referring to TV Audio Swap when you speak about watching TV while using headphones, because that is exactly what TV Audio Swap is by definition.  But regardless, your understanding is incorrect.  Both the Ace and Ace Ultra can have two separate pairs connected to the same Sonos soundbar for watching TV sources via TV Audio Swap.  

From: https://support.sonos.com/en-us/article/listen-to-your-tv-with-sonos-headphones-tv-audio-swap

A second set of Sonos headphones can be added to the same TV Audio Swap session by pressing and holding the Content Key on another configured unit.

. . . 

A second unit can be added to the same TV Audio Swap session by selecting Join on the Sonos headphones info screen.

This feature was not available for Sonos Ace upon release, but has been out for months now.  You may be looking at info from the initial rollout.

Unless the OP is referring to connecting two Ace units to the TV via Bluetooth?  OP, could you please elaborate what you are seeking?

Thanks jgatie. I was unaware they had added it and put it under that label. Perfect!

I think the confusion may be between the terms ‘audio linking’ and ‘TV swap’, which in general can be misconstrued for each other fairly easily. Kind of like TruePlay and Quick TruePlay. Similar terms, similar feature sets, but entirely different things. 

Your understanding is incorrect