An alternative could be the establishment of an RMZ
Complicated at Carlisle by the proximity of Spadeadam. If transient traffic was required by the RMZ to speak to non-radar controllers at Carlisle that would mean they were not speaking to Spadeadam or the LARS provider for the area, Newcastle.
But Loganair are THE experts in commercial ops into non-radar airports in Class G, so I'm sure they will be giving good advice to Stobart.