How to Update the two optionset Values On Change

Dear Experts,

I have Travel Plan Entity In Travel Plan Entity i Have pcl_travelplanstage two optionset attribute it contains planed and actual values

and am having 1:N Relationship with appointment Here also am having pcl_travelplanstage two optionset attribute 

now i want to update the value from Travel plan entity to Appointment Entity

Thanks and Regards

Shankar