Automation/Butler due date trigger sometimes not firing

Hi all, we have a Butler/Automation rule as follows:

the moment a card in list "X" is due, move the card to the top of list "Y"

It has been working ok, but on occasion we see the card fail to move at the due time. Any ideas why this might be?

I have spotted that the if the card is marked as “due date complete” then the rule does not consider it as a valid card to move. This seems odd behaviour to me as there are explicit options in Butler/Automation to filter on “a complete due date” or “an incomplete due date” - so my assumption would be that selecting “a due date” should ignore the completeness state. Anyway that is an aside.

We have seen this rule fail for cards that are not marked as complete as well. I see no errors or warnings in the usage log for the account. We have a Trello Enterprise account, I dont see any quota there that we could be hitting either.

Any thoughts would be appreciated.