Originally Posted by
FlightDetent
There are places when it is really helpful if you guys say so, and the other unit takes our word for it.
Yes, but it has no real meaning. If you tell an ATC unit that the previous unit has 'released' you that means squat. Sure it implies that the previous unit has transferred you and once beyond the defined TOC point the next ATC unit can disregard any constraint that the previous unit may have had, but it does not mean that in reality. Cross boundary issues are defined by LoA between the ATC units/ANSPs involved. A typical example is where you are crossing a boundary, but just inside the area you are exiting there is crossing traffic that does not affect the new unit you are entering, but is still a restriction on your operation until the required lateral separation is achieved. The new unit knows nothing about that conflicting traffic so if you tell them that you are 'released' and they change your level to or through the conflicting traffic then TCAS will be your saviour.
So I'll repeat - the term 'released' is an anachronism and has no place in modern air traffic management. Be very, very cautious if relying on any such statement.