Angular Request Properties - alternate to %UserUID%

v9.0 LTS - jumping to v10 LTS early next year

I was using '%UserUID%' in the condition query for a table lookup, but I noticed that this is always the authenticated user even if they are requesting on behalf of someone else.

Is there an equivalent %% parameter that can be used in SQL conditions that represents the user requested for?

At the moment I have another hidden field that is populated based on "If Provider.Contains("UID_PersonOrdered") Then ", and then reference via $PC(name)$ in the SQL condition but it has poor performance and is just plain nasty.