1999 & 2000 Japanese Neo Genesis PSA Labels

I have a full PSA set of JP Neo Genesis holos and for the life of me I don’t know why some of the labels say
“1999 PM Japanese Neo” and a few say “2000 PM Japanese Neo”.

Any reason for this? None of the holos are from the Premium File #1, they don’t have errors/or are corrected (to my knowledge), and they don’t have the copyright date on them (as they should for early Japanese). I’m stumped.

Do y’all know why? Or is it a PSA mislabel sort of thing? They are all 4xxxxxxx certs or newer