A=1998
B=1999
C=2000
...
R=2015
I know you can look this up on the interweb:
https://millenarywatches.com/panerai-serial-numbers/
I've always liked this one, for the older models:
https://www.paneraisource.com/milles...ordering=refno
Shall we guess what happens after Z (2023)?