[TxMt] Scope issue with 1.5.6 (1414)?

I'm trying to write a command that reformats Python triple-quoted (""") strings. The scope of such strings is:

source.python string.quoted.double.block.python

when I create a command that has:

Input: Selected Text or Scope

and said scope as the Scope Selector, then run the command with the cursor inside a triple-quoted string, the entire document is fed to the command instead of just the triple-quoted string (the current scope).

I've confirmed the scope via TM_SCOPE. Clearly I have the Scope Selector correct else my command wouldn't be activated (I've bound it ^Q).

Any ideas?

j.