If they are using a Julian Code, the number sequence can be interpreted as follows:
1st two numbers=year of production
2nd three number=numbered day of the year
final numbers=batch for that day
SO…the number 0513504 means that bottle was manufactured in 2005 on the 135th day of the year and it was part of the 4th batch of the day.
You’ll know immediately if it is a Julian Code if the first two numbers are a zero followed by a 5, 6, or 7 (I would hope nobody has product out there that is more than two years old, soda pop in particular).
If the number doesn’t follow this format, you’re on your own.