I think your post is broken or something, I can’t fully understand what you mean. If I guessed it correctly, you want a API that can return the list of programs for a specific station, is that right? To be honest I don’t think it’s worth adding this feature in the firmware — it can be easily done in your client software. For example, if you use Javascript, you can easily write some code to strip away programs that do not include a specific station.
Also, it will help to understand your application. Why are you using the /jp command directly, instead of using the GUI to check programs?