Hey @kirkie4567,
Thanks for sharing the context! It sounds like Scheduled workflow is still your best bet.
If it’s a monthly activity where items are being updated, then you should set a Scheduled workflow to run monthly (or any other frequency that better suits your process). Add a Query action to fetch all items that are considered ‘incomplete’ - This should pull everything that was added in the current month, but also look into the history for any items that are still outstanding. If there are no items, end workflow.
Otherwise, unfortunately there is no way to group or batch Sharepoint events in the way you’re hoping for.
Let us know if you have any further questions!
Kate