What is the output bundle of the Aggregator when: (1) there are updates, and (2) when there are no updates?
Could you adjust the Text Aggregator such that the output is a zero-length string when there are no updates? If yes, you just need a router, a clone of the Outlook module, and two filters.
Hope this helps! Let me know if there are any further questions or issues.
— @samliew
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