Yes tks JF I had not really considered yr correct analogy in jumping from the Lincoln (in UK production) or B-50 Washington (in UK service) to the Valiant (V bombers in general...!) - a massive technological and logistical leap in every way...
I think it shows the great skill in design and production we once had and apparently have now let die in last decade which will be hard to resurrect and probably never return
I make an assumption based on my own observation that Valiant was developed early on for secondary purposes such as tanker and ECM as it was surpassed and seconded by the slightly later in service Victor and Vulcan in the strategic bomber role