How does the conversion work?
The 18-character ID adds a 3-character suffix that encodes the case of each character:
- Split the 15-char ID into three 5-character chunks
- For each chunk, create a 5-bit number where each bit is 1 if the corresponding character is uppercase
- Map each 5-bit number to a character using: ABCDEFGHIJKLMNOPQRSTUVWXYZ012345
This allows case-insensitive tools to preserve the original case information.