Searching for Destination London (all Airport)
It seems that when you search for flights to or from London(All Airports) on easyJet, it doesnt give Southend, even though easyJet has it classed as a London airport.
This has not always been the case, and I would say it is some sort of glitch, and doesn't help SEN to promote its services.
Take for e.g. BFS which is being cut down to daily on most days doesnt get represented when the budget traveller searches for London (All airports), as the SEN option wont come up and quite likely people who dont know of it, wont check it separately.
Be good if this was sorted out.