My landline phone (BT 6500 Cordless Phone) rings if you have hung up but if the person on the other line hasn't hung up after 5-10 seconds which is great if you

My landline phone (BT 6500 Cordless Phone) rings if you have hung up but if the person on the other line hasn't hung up after 5-10 seconds which is great if you accidently turned off the phone (my parents do this all the time) and in this instance for this case.