Fascinating insight, many thanks for the info. I've read bits and pieces in various places re the cruisers, and it seems in 1940 there was capacity for 10 but none were orderd due to other priorities. Similarly for 1941 and 1942 there was a desire (capacity?) for 7 each, including at least 4 of the 8 inch designs. I have found in Conways some good sumaries as to the wartime programs, but frustratingly it seems to only include ships that were only laid down, not planned but cancelled. Do you have by any chance some short summary of the complete wartime programs including ships by class and including planned but never laid down ships?
It seems there was cruiser planning for 12 Minotaurs and 5 Neptunes as well as 8 inch CAs (Admiral class?). So in this ATL, we can assume that the cruisers OTL delayed by the war (Didos and Fijis) could probably be finished one year early at least, and the subsequent classes/hulls be brought forward a similar amount? Also, likely the Minotaurs might be a 12 gun design.
Anyway i'm probably harping too much about these blimming cruisers, though it's interesting to ponder what the japanese could have faced in 1944-45, also because it seems the british built an obscene amount of cruisers compared to Japan. Though the americans i guess were just as "obscene" in OTL.
Back to the bigger combatants, so we probably expect another 2 Implacables to be laid down in 1940-41 ready in 1943, and another 2 Implacables or perhaps Irresistibles in 1941-42 (ready 1944-45 at best). There will be probably 6 Lions building by 1942 plus Vanguard, though the war will almost certainly result in delaying/cancelling the last 2 Lions, as well as many of the 20 plus cruisers building under the ATL 1940, 1941 and 1942 programs, or on order.
So it seems in the all important CV matchup, at best RN would have 10 fleet carriers in 1942 (Ark, 3 Follies, 6 armoured), plus Eagle and Hermes with roughly 450-475 planes on board at best, faced with the 6 KB carriers, 2 Junyos, Ryujo, 2 Zuihos with something like 550 planes. The RN will only add another 4 Implacabels or Irresistibles by 1944-45, plus whatever emergency CVL would be ready under a 1942-43 wartime program. Still to me it seems the RN on it's own will have nothing like the USN crushing fleet carrier superiority in 1944-45, not to mention many tens of CVEs.