Trojan Battery Age

Looking at some Trojan L 16 G AC (Motive) batteries. They are stamped with a F3 code. That would be June 3. But is it 2013 or 2023?
Thanks

Talked with the Trojan tec today. Said it could be either one based on that. Also a 12 digit mfg code to give an exact date April of 2023. Good! Then I find out they haven't been charged in at least six to 9 months!!! They have to be seriously damaged?

Bump for op.