I am adding the resource to the SA in the following manner:
ActivityParty resParty = new ActivityParty();
resParty.PartyId = new EntityReference() { LogicalName = "systemuser", Id = appt.new_PhysicianAssigned.Id };
resParty.ActivityId = new EntityReference() { LogicalName = "serviceappointment", Id = appt.ActivityId };
resParty.ParticipationTypeMask = new OptionSetValue() { Value = 10 }; //resource
myContext.AddToActivityPartySet(resParty);
appt.serviceappointment_activity_parties.Add(resParty);
How would I remove all the resources and only the resources for a given Service Activity?