The RAF itself illustrated the utter unsuitability of the Airtanker PFI contract when it tweeted this picture

https://cimg3.ibsrv.net/gimg/pprune....683429a750.png
Royal Air Force fighter aircraft have begun a four-month @NATO Air Policing mission in the Baltic region after replacing their German @luftwaffe colleagues. Read More: http://ow.ly/X0JQ30oCLGj #RAFOps #WeAreNATO

So, according to the RAF, its Typhoons can refuel from a Luftwaffe A400M, but not from its own Atlases. OK, I know the Typhoons are not actually connected here, but presumably they could be.

I give up....

airsound

Hypothetically speaking, if the RJ was trying to depart Waddo for a sortie but was prevented from taking off with full fuel due to the runway, I assume it would be a USAF Tanker that would provide the fuel.

I could be wrong (and happy to be corrected if I am) but I seem to recall that the contract states the MoD must use AirTanker, but can use other national or international assets if no AirTanker aircraft is available (hence the image with the German A400M here). Perhaps there is scope there to equip some Atlases with AAR kits to service RAF/RN receivers for when and where there are no Voyagers available (in the Falklands or Baltics, for example)?

It's not hypothetical, that's what they do.