Yeah I know this is old but....
Why is L18 also called L-85?
Why is LDA002 Para Pleco also called an L075, L124, and L301?
These fish are still in a major part of the discovery phase. Different people are "identifying" them and giving them names and L numbers. So that leads to multiple names AND L-numbers being given to the same species. In the case of phantoms, they were "discovered" in completely different areas, and had completely different colors at the time. That would lead to someone classifying them as two different species. They are just NOW starting to identify the various species by DNA, to figure out which ones are the same species as others, but different variations. But that is still a work in progress.