The last time we flew VA from LGW the priority boarding was non-existent, you had to push your way to the front holding your boarding pass up high, encountering the wrath of economy passengers shouting 'do not push in' and do you think you have a different ticket to me, is this still the same or is the desks at the gate different for UC and PE passengers, as it can get a bit out of hand if your in UC or PE
I've always classed the priority bit as checking desks and getting to the gate but not actually boarding from the gate unless you are there for the first boarding call.
If arriving after boarding has started, we usually just wait our turn on the jetty with everyone else
The check in and entry to the gate area as well as the boarding part (if we are there early) has always worked very well for us when flying upper from gatwick
David
Should add that the priority lane outside the gates is usually clearly marked and well policed by the checkin staff.