REST API Need to Filter Activities by Child ActivityAssignee LastUpdateDate
We are trying to filter acitvities based on the LastUpdateDate.
This works fine where the Acitvity Object has been updated.
However the problem is that when an activity assignee is modified, the LastUpdateDate is not set on the parent activity record.
We need to query activities based on the LastUpdateDate of the child ActivityAssignee record. How do we represent this in REST? have tried setting the q=ActivityAssignee:LastUpdateDate>2021-01-07T01:55:37.637Z.... however this fails