Merge PDFs and save merge list

I have lots of small PDFs. These are mostly about two pages; some are a few more (up to, say, ten).

I wish to produce several different collections of subsets of these into bigger PDFs; for instance "collection1.pdf", "collection2.pdf", etc. (One major collection would be about 150 pages total). I understand that pdfforge would allow me to do such merge activity. Is that correct?

But I also then wish to save that collection data (e.g. collection1.pdf comprised small files a,b,c; collection2.pdf comprised small files p,q,r; collection3.pdf comprised c,b,p,q; etc.). This enables me to return in a few years and produced revised editions of the collections, based on the original, but being able to adjust the contents from those stored lists.

Can pdfforge enable that sort of activity? Could you point me to an online manual page that describes this, please? Thanks.