For the B-29 perhaps the most important difference isn't the development timeline but where they are deployed initially.
Not the costly and ineffective basing in India and China as in OTL. There are better places becoming available. The Philippines must be liberated anyway. Expedite the liberation of the island of Luzon including Manila.
Luzon could be cleared out by the time the B-29s are ready. This would make Clark Field available for their use. With the harbours of Manila Bay a short distance away by railroad and road supplying a few B-29 wings isn't a major difficulty there. From Luzon B-29s can reach all of Japan and Korea and Manchuria. There is no need for the bloody campaign to capture Saipan and Tinian.
Not the costly and ineffective basing in India and China as in OTL. There are better places becoming available. The Philippines must be liberated anyway. Expedite the liberation of the island of Luzon including Manila.
Luzon could be cleared out by the time the B-29s are ready. This would make Clark Field available for their use. With the harbours of Manila Bay a short distance away by railroad and road supplying a few B-29 wings isn't a major difficulty there. From Luzon B-29s can reach all of Japan and Korea and Manchuria. There is no need for the bloody campaign to capture Saipan and Tinian.