How do I check when a date field in Zoho Projects has been changed from a flow?

How do I check when a date field in Zoho Projects has been changed from a flow?

I am trying to create events in a shared Outlook calendar based on a custom date field in Zoho Projects.

And I have a trigger to create the event with the date from this field when the project is created.

But if this date changes in Zoho Projects, I need it to also update the data in the Outlook calendar but I can't figure out how to detect if a field has been updated and then to modify the date in the existing calendar event.

I have set up another flow using the Project Updated trigger but how can I check if the field has been modified?