Yeah, OKH loved to have that great, detailed initial plan with a lot of ¯\ (ツ)/¯ fluff for contingencies later in the timeline if things went wrong. By they aren’t that different from the US Army planning culture in that regard.
The IJA were all about writing an awesome conceptual plan and then figuring out the details while executing it. ;)
This led to things like Adachi’s IJA 18th Army HQ issuing orders to troops in New Guinea to plant crops to supplement rations so they all wouldn’t starve to death.
You know you are in dead and in hell when you wake up in the morning, go to the daily briefing, and receive word that HQ has ordered you to grow crops.