Hi Rip Van Leech
I've just been through and spoken to one of our holiday advisors who has explained this in a bit more detail for me.
The regional flight supplement of £79 is the brochured supplement for flying from this airport on this tour, date and on the allocation that we have available when we put together the tours. However, at the time of your booking there were no flight seats available from Manchester and we had to request an additional seat. The flight supplement (£49) is the additional cost that the airline have charged us for this seat.
Had you of pressed the book now button on the website, your booking would have gone 'on request' as part of the booking (the flights), cannot be confirmed at that point in time. One of our advisors would have contacted you to advise of the additional supplement.
I hope the above helps.
Kindest regards,
Julia