Search request doesn't return appointment instances

[evk]

I request appointments like:


{"Body": {"SearchRequest": { "calExpandInstStart": 1469998800000, "limit": 500, "sortBy": "none", "offset": 0, "types": "appointment", "query": {"_content": "inid:\"10\""}, "_jsns": "urn:zimbraMail", "callExpandInstEnd": 1470517199999}}, "Header": {"context": {"authToken": {"_content": {"_content": "TOKEN"}}, "_jsns": "urn:zimbra", "format": {"type": "js"}}}}

Appointments in response doesn't have instances - inst filed is missing.

The same query issued by zimbra mail web browser app has instances in responses ( I see it via developers tools / network )

How can i obtain instances ?

Thanks.