Probably just me adding 2+2 and getting the wrong answer, but, might this be something to do with one of the conditions for bidding for the ABZ and EDI slots that the airline is not allowed to have any leased out slots and these were brought back to allow Virgin to bid? If so Virgin have the choice of running 3 new long haul routes, finding more airframes to increase frequency on existing routes or "slot sitting" on a short domestic route and making political capital from the situation.
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