[toppcat]

I think the answer is they were still composing the uncut sheets in rough numerical order and the first three (which would go no higher than #396) were composed and printed first. The change was then ordered at the end of the first run of these sheets. The error above those numbers on the #599 rookie card was likely just overlooked the first time around. Based upon the two "correct" versions of #599 at least three print runs came off the presses. It seems likely to me that each sheet's run was completed before the next run or new sheet batch was started. There had to be some order to the process just from knowing how Topps went about their proofing process.

I seem to recall the Washington cards were not available in all parts of the country, possibly from a newspaper article at the time. Again, going from memory, Topps had three main distribution centers in the US around this time, so I wonder if one run was meant for each distribution center. As kid collectors in 1974, we were very aware of the errors on Long Island so they have always been popular.