Anyway, getting back to the point of the thread. I dunno what, if anything the Chesapeake is going to do other than provide the British with yet more aeroplanes they will lose on Japan's successful campaign in the region, that is, if they are not destroyed on the ground in raids against the airfields in advance of the invasion. Nevertheless, more airframes probably couldn't do the Allies any harm, but it does depend entirely on how effectively they are used once they get there.
I'm not sure they'd be able to do much against the Japanese in those jungles given the limited training time over the terrain they're fighting over, either. CAS wasn't so highly developed at that stage, I think.