Apparently, London INFO and the London FBU are now refusing to activate (i.e send a DEP message) for VFR flight plans that were filed using AFPEx.
A couple of days ago, a friend and I planned to fly to Le Touquet. We filed both the outbound and return FPL's using AFPEx and addressed them according to CAP550.
Once airbourne, we called London INFO and requested that the FPL be activated. We were told that this was not possible due to the FPL originating online. We didn't argue and returned home.
After making a few phone calls we were given a very "loose" explanation. But I'm still not sure I fully understand. Apparently, when flight plans are filed by the FBU, the plan (and addressees) are saved with the callsign. When a DEP message is sent, they simply copy the addresses from the original FPL. If you file using AFPEx, they don't have a copy of the original addressees and so have to hand address the departure message which is apparently too time consuming... Utter madness!
So what are the options? Sit at the holding point with your laptop switched on?
