67th Tigers, the British carriers were fewer than the American, carried fewer and less effective aircraft and there still won't be much industry which they can target at sea.
In December 1941, noting no WW2 to sink half the RN carrier force:
RN
Argus - 18 (in training role, not counted)
Glorious, Courageous and Furious - 48 ea
Eagle - 21
Hermes - 20
Ark Royal - 64
Illustrious, Formidable, Victorious, Indomitable - 54 ea
= 10 Carriers with 465 aircraft
USN
Atlantic Fleet
Ranger - 66
Yorktown - 72
Wasp - 72
Hornet - 75 (trials)
Pacific Fleet
Lexington - 59
Saratoga - 62
Enterprise - 71
= 7 Carriers with 477 aircraft
IJN
Akagi - 72
Kaga - 81
Soryu - 63
Hiryu - 64
Shokaku - 72
Zuikaku - 72
Hosho - 21
Rjuyo - 37
Chitose - 30
Chiyoda - 30
Zuiho - 30
= 11 Carriers with 572 aircraft
Overall the Anglo-Japanese in that TL had a 3:1 advantage in a/c hulls and 2.2:1 in carried a/c. In terms of strike aircraft the disparity is far greater, as the USN carried very large scouting contingents.
The UK on her own has mere parity with the no. of embarked a/c, but has more decks.
In this POD British bombers will be too few to have a significant effect when the war begins. Just take a look at the numbers of RAF Bomber Command OTL in September 1940 after a full year to gear up.
The RAF had a fairly large number of high altitude bombers in 1939, and the number was increasing with the introduction of the Manchester.
Also, I really hope you aren't peddling that nonsense again about Japan landing scores of divisions on the West Coast.
Not me. That's the USN's war planning division. Personally I doubt they could land much more than a single army corps, not because of their logistics but because the army was tied up in China. Of course, this would mount a serious challenge to an unmobilised US which has 3 usable infantry divisions (1st-3rd) with their transport, artillery etc.
That's basically the case with an unmobilised US. They have manpower reserves to build forces later, but from a standing start they'll have a hard time invading Canada, let alone responding to any Japanese attack on California ITTL. Later things may be different....