Unfortunately, Celestia is also completely booked up for the week. Some of the Nobles had organized an Airship to go on a cross-Equestrian-Tour. Not a terrible idea in of itself, and often a lucrative expenditure for the non-pegasi... until they decided that floating directly over the Dragonlands was a great idea. And one can guess how well the Nobles handled that whole 'getting burnt out of the sky' situation. Nopony was badly hurt, thankfully, but it was definitely an unpleasant political situation that left The Princess up to her chest-fluff in problems.