You are right. As I type this, the first thread is entitled SBP 1289. It could be absolutely anything from anywhere.
I have concluded that there are little groups of those who are 'in the know' and don't really want others to enter their world for some reason.
Some time ago members helped me to compile a list of acronyms for different puzzles but I found that, although I had the list, the acronyms rarely appeared.
Hey ho!