Just recently, The new PDFs for May have been released. And for $25K Pyramid, it says "NEW" in the episode column. I foresee four possibilities:
1) It could be episodes that have never been shown on GSN before.
2) It could be from when the show was called The "NEW" $25,000 Pyramid, from November 1982-January 1985. The first season, perhaps?
3) It could be from any of the episodes that have never appeared on GSN before with the word "NEW" in the title, from late 1983-early 1985.
4) Maybe I'm reading into this too much.