Your MC would be the best to answer that question because they are most intune to your situation. In all likelihood even though “student loan” is just one type of debt you would probably have to write a loe for each individual loan.
It’s probably better this way too. The underwriters don’t look at debt categories they look at transactions. So if you put everything in one letter the underwriters may come back with more conditions or clarifications. Ask your MC see what they say. But really is writing a multiple loes that problematic? It only takes 5 minutes and will help you out immensely in the long run by getting you that house you want.
Nelsont nailed the answer again! Bottom line, separate letters are always better, and shouldn’t be a problem since they are going to be essentially using the same “template” and are all addressed “To Whom It May Concern”. Only the details will change from letter to letter. It also fits in with my mantra of “better twenty pages too many than one too few”.