tiger - there's another issue to consider. At the moment, with flying split across Newcastle and DTV, it's somewhat fragmented. In effect, DTV is a fortress airport for KLM - there's sufficient demand for only 1 network carrier so nobody else can break into the network flying market at DTV, meaning KLM get all the business which doesn't already leak to Newcastle.
If DTV loses KLM, all flying in NE England is then concentrated in Newcastle, making network flying from Newcastle a much larger and more attractive market.
Would Lufthansa perhaps be tempted to either scale up their Newcastle-Dusseldorf route or perhaps even launch Newcastle-Frankfurt ? Alternatively, might Emirates or SAS increase capacity ? If so, this could take a large chunk of NE England centric revenue away from KLM