No, I did mean Vulcan 1.
I agree the basis for this, which I will relate, is tenuous.
In 1967 the Recognition Journal mentioned the Vulcan BPK1. When I challenged this I was told that there had been a tanker variant.
Now this might have been a plan that was not proceded with or it might have been a formation trial to test fesibility or whatever. If they were looking at a tanker similar to the Valiant it would have been a bomb fuel pack, single hose etc and clearly much further forward.
The tanker plan may have been associated with the Airborne QRA trial which was also abandoned as we simply had insufficient assets compared with SAC.
Maybe one of the really senior V-force crew may wish to add something.