Dataflow Gen2 Max Effective Date as Parameter

Hi,

I have a Dataflow Gen2 where I am first querying the Max Effective Date from a table and then trying to use that as a parameter in a query later on in the flow (see screenshot).

I am running a query (that only returns one row with one column) and getting the date value from that row/column using an aggregation. I am then referencing that in the next query as a "reference query" value.

The preview in the 2nd step actually works and I can see my SQL Server receiving the date parameter correctly... and the data preview even populates on the 2nd step with only the data I need, but I keep getting the following mashup error when I publish and run:

We cannot apply operator #{0} to types #{1} and #{2}., Underlying error: We cannot apply operator < to types Table and Date. Details: Reason = Expression.Error;Message = We cannot apply operator < to types Table and Date.;Detail = [Operator = "<", Left = Table.FromRecords({}), Right = #date(2008, 10, 31)];Message.Format = We cannot apply operator #{0} to types #{1} and #{2}.;Message.Parameters = {"<", "Table", "Date"}

Is what I am doing not supported or did I do something wrong?

Here is the advanced editor text for first and 2nd steps: