Here's a hypothesis. Planners hoped that if the Kanto Plain and Tokyo were taken, Japan would finally surrender. But there was a vague contingency plan (at least I've never seen a formal plan) to continue pushing if there were continued resistance. So, these units may be training and staging for that contingency. I did a quick check of 2nd Infantry's Wiki and on VJ day they were in Texas training to go to the Pacific.
Doesn't that sound like a nightmare? More mountain fighting against fanatical resistance on Honshu?
http://upload.wikimedia.org/wikipedia/commons/f/fa/Operation_Downfall_-_Map.jpg
Reviewing the map above for Operation Coronet, I see 1st Army being the entire organization of what is currently 10th Army on Okinawa. Only the 1st Army HQ has been substituted. Other than the armored corps in floating reserve, I see no units from the ETO.
Am I missing something, or is this map inaccurate?
