"Stan Prevost" wrote in message
...

Interesting. I never heard that before. So a TRACON controller cannot
change a clearance without calling center to do it?


It's a flight data processing issue. A terminal controller cannot amend a
flight plan in the computer if the host center has auto-acquired a target on
that flight. The revised clearance must then be manually coordinated. The
alternative is to suspend the auto-acquire feature, which will then require
the center to manually start a track on aircraft that depart from airports
where the center provides approach control services. Suspending the
auto-acquire is the way to go, starting a track is quick and easy and is
more than made up for by the reduced manual coordination.