At a Jazz Times convention in DC around 1981, I was privy to a discussion about this date. Participants included Keepnews and Max. Orrin said they never got a complete take and the record was a "splice job". Max said this was Monk's way of getting the musicians some extra money via "overtime".
I thought this was Roach's way of "sticking it to the man".
Keepnews was not a happy camper.
Later, at the bar, I thanked OK for the Ernie Henry dates and he went off into the world of "people he lost money on".