Interesting
When I tried to run a post create plugin on any activity (i.e. phonecall, task, email, etc) that time i was unable to get the regardingobjectid in the target entity.
then I looked into the Audit history of this entity and found out that at time of creation we don’t get the “regardingobjectid”, internally some workflow of something runs and it creates one update audit history, and i found out that update audit history really update the regarding object id.
then i registered my post create plugin to post update plugin and this solved my problem.

























