You need to look at the history of the the airline and how it developed to understand why the HQ is where it is.
The question (well, non-question really...) is why on earth would the airline consider moving it's HQ, with all the upheaval and cost that would entail? What would the business case be? The only reason I can think of is if they are made an offer they can't refuse by an official body with loadsamoney to chuck around? Don't think there are many of those of those around at the moment, so dream on...