Have to concur that sadly PIK seems to be very much between a rock and a hard place with Ryanair being the only sked pax operator. Even if APD was abolished, then surely (don't call me Shirley...) that would also apply to GLA and EDI airports? Unless of course, Holyrood &/or Brussels(!) was able to grant some sort of "EU development zone" exemption status to PIK?
My own viewpoint is that the APD scheme needs a radical review anyway, perhaps being retitled Heathrow Environmental Airport Tax (HEAT). The market at LHR could more easily absorb this tax and dare I say, perhaps LGW too?