I'm reasonably sure that a Nav with a PPL can also fly AEF in a Tutor - I know one!
I also think that Vigilant is probably now doomed. The extension for the engines from 2015 was for 2 years to 2017. With 2016 fast approaching then I suspect maybe a small number of low-houred Viggies will fly maybe at just Syerston? Sadly the engine extension has been squandered with the 'pause' and I believe it's unlikely that Grob will extend again...
As for Viking. I suspect there is still a long haul ahead. There is still not a single one airworthy nearly 20 months down the line. Also the newly bought Skylaunch winches do not have a clearance to operate the Viking from. Some test flying and amendment to the RTS and aircrew manual will be needed. I was hoping that this work would have been done during said 'pause' but I have seen no evidence that it has - anyone know for sure?
Seeing as it is the 75th Anniversary of Air Cadets in 2016 then they are cutting a bit fine to have something to crow about!!!
LJ