Error using Expression.Evaluate & #shared for dynamic query refrence

I have a number of different finiancial queries for each quarter and I want to be able to choose which to pull from dynamically.

I attempted to accomplish this like so:

Source = Expression.Evaluate("LY-All Branch Summery-Q"&Quarter, #shared)

Unfortunatly this threw an error at me:

Expression.Error: [1,8-1,14] Token Eof expected.
Details:
[List]

To Diagnose this I hardcoded the query name, and in another step referenced the query with the more common #"Queryname" approch.

let    
    Source = Expression.Evaluate("LY-All Branch Summery-Q1", #shared),
    Source1 = #"LY-All Branch Summery-Q1"
in
    Source1

In this query If I go to step 'Source" I get the same error as above. "Source1" however gives me the query as expected.

What am I doing wrong here?

Thanks in advance

Joseph