My theory is this:
They're doing what they did way back before the 1954 series came out: Replacing damaged sheets with sheets bearing the same numbers.
When a sheet gets damaged, they pull it, number a blank sheet with the numbers of the sheet that was pulled, and put this new sheet between the top two sheets (the insert position, between 000/001, and 500/501).
Several members will agree that the Bank of Canada has been trying for years to get us collectors to mind our own business and get off the idea of replacements, inserts, brick hunting, etc. The asterisks were too identifiable, so they tried X notes. That plan had roughly similar success. So they moved to insert notes in the Bonin/Thiessen era. This threw us off for a bit, but once collectors picked up the scent again, the battle renewed itself with even greater intensity as the hunt for inserts continued. Now in what I expect is rather costly for them, they seem to be replacing damaged sheets with sheets bearing the numbers of the damaged sheets. This means no identifiable replacement or insert notes PERIOD. Every number in a run gets issued unless there is a broad gap in production, as can be assumed from several examples we now know about.
The suggestion that these are Quality Control Inspection Notes doesn't fly with me. Why are they all of a sudden doing this when they've been making banknotes for over a century?
If I am right in my theory, this will eliminate the "A" designation on all further Charlton numbers for Canadian government bank notes, and it will mark the end of an era for one of Tom's sweet tooths.
Logged
BWJM, F.O.N.A.
Life Member of CPMS, RCNA, ONA, ANA, IBNS, WCS.
President, IBNS Ontario Chapter.
Treasurer, Waterloo Coin Society.
Show Chair, Cambridge Coin Show.
Fellow of the Ontario Numismatic Association.