Could be charter, or they could have bought seats on the flight. TCX have done that with the LPA. Jet2 want to do more charter routes anyway from NCL, including long haul fom about Aug 08 apparently. Rumour mill is VERY strong with rumours of the 767-200ER arriving in Aug, apparently it will be announced in about Feb.
More importantly, as I will no doubt be operating the flights any chance u know the flight times? Im hoping its not a nice deep night flight but I know it prob will be.