I know only some elements of the code for tracking parcels, because I often order something on the Internet. For example, the letter part represent the country of the recipient and the country of the sender. I don’t know about the meaning of the numerical part. Will the ability to track parcels change if the 12 character code is changed to 17 character code? I always used https://pkge.net/ for tracking, the ability to track was more important to me, and the service always worked, so I never paid attention to the number of characters.