>>Dragan - Very interesting thought re: collate sequence. I need to wrap this up this morning but will do one more test run as is to test out that theory.
>
>Very simple to test - just add
>

... collate "machine"

>(must have quotes!) in the index command. See if it fixes it.

Thanks. What I did was record a LIST STATUS (which includes COLLATE SEQ) to text files before and after the REINDEX "fix" and compared them. Collate was MACHINE in all cases, but the index was no longer set as the MASTER index tag. I've added SET ORDER TO indexTag as part of the REINDEX "fix" and the problem no longer appears.

Would love to get to the bottom of this--maybe someday I will--but that day's not in my immediate future as I'm being bombarded with projects and this rabbit hole has already swallowed tons of hours.

Thanks again, Dragan and the rest. Very much appreciated!