I've read that the first UK nuclear powered submarine HMS Dreadnaught (S101) was powered by a US made reactor, but that subsequent UK ships of that kind used UK-made ones. Wikipedia claims:
During Dreadnought's construction, Rolls-Royce, in collaboration with the United Kingdom Atomic Energy Authority at the Admiralty Research Station, HMS Vulcan, at Dounreay, developed a completely new British nuclear propulsion system. On 31 August 1960, the UK's second nuclear-powered submarine was ordered from Vickers Armstrong and, fitted with Rolls-Royce's PWR1 nuclear plant, Valiant was the first all-British nuclear submarine.
Amusingly, their other page on the PWR reactor says
Nuclear reactor designs, operating methods and performance standards are highly classified. Details of this type regarding the reactors are not available.
In view of the current AUKUS dealings, after the Dreadnaught, has the US transferred or at least authorized transfer of any more such technology (reactors or designs) to the UK? Or has the UK been using "completely new" designs thereafter, as far as publicly available information goes?
Further down the latter wiki page, there's an even more confusing sentence
PWR3 is a new system based on a US design but using UK reactor technology.
Is there any more detailed public information what that means in terms what "US design" and what "UK technology"?