CaptKremin, how could you make the route a PSO one unless the successful tenderer also had the necessary LHR slots and was prepared, one assumes, to shelve any other uses of said slots in favour of SNN?
Well I guess it would work like this:
Bertie: Keep the SNN-LHR route
Dermot: Can't afford it, sorry.
Bertie: OK, here's xxx* million subvention.
Dermot: Done.
End of story.
*Insert whatever figure is sufficient to compensate for return of the leased slots, plus a bonus subvention to make the route sufficiently profitable.