Originally Posted by
fumje
The linked article says
The United inflight announcement about lavatory usage will be adjusted as a result, and flight attendants are now instructed to say “please use the restroom located in your cabin when possible.”
So from I surmise, there will not be an invitation for Y pax to come forward to F; rather, the FAs will not stop them if they do so.
And I'm sure that the FAs will be diligently monitoring the curtain to say this to every passenger who comes up.
As if I didn't need a 15th reason to avoid UA travel, here is one anyway. (mild hyperbole)