Hello @Felix Valerio
Thanks for reaching out!
Please refer this documentation to know how Delta query is used for change tracking. Using Delta query, you can get new, updated, or deleted events in a specified calendar or within a defined collection of events.
Removed instances are represented by their id and an @removed object. The @removed object may include additional information about why the instance was removed.
Updated instances are represented by their id with at least the properties that have been updated, but additional properties may be included.
Newly created instances of a supported resource are represented in the delta query response using their standard representation.
Please note that every time the event is changed/updated, the property ChangeKey changes as well.
Hope this helps.
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