In response to mockingjay, Jet2 and Jet2holidays run in unison, and on the same booking system. Jet2 don't sell seats to Jet2holidays, but as they run on the exact same booking system, it means that Flight Only and Holiday pax figures can appear rather different to other airlines.
Not true. Jet2 appears as a flight supplier in Jet2holidays booking system with an equal "status" to the suppliers of the airport transfers and the hotels or apartments. Flight only bookings do not appear anywhere in the booking system used by Jet2holidays and changes made to a flight booking belonging to a Jet2holidays package in Jet2's booking system do not feed back to Jet2holiday's booking system.