Unfortunately there is another significant adverse factor creeping in, to further undermine expansion, in that historically a significant number of Scots from North of the Border supported routes that are now being aggressively marketed / available closer to home....
Interestingly the recent news as to the potential sale of a 49% shareholding by an "investment fund" fits in with my take that the sale is simply a financial one, in that an appraisal has taken into account the significant potential gain and high market capital valuation due to the achievement of recent high profits, has likely concluded to sell at the top of the market. Falling pax numbers in future would adversely effect potential profits. Furthermore I do not see new investor(s) contributing much, as they would be buying in at a significantly higher valuation, with the ensuing pressure to drive dividends for their investors as opposed to reinvestment in airport infrastructure.