with 55 i did it all the time, as i wanted the negative to be the final product not the print that just came along for the ride , "so to speak"
How did you do it? The negative is ISO 25, and the print 50. If you exposed for the neg, you overexposed the print (and vice versa). By itself, that is just an exposure change, not a push or pull. How did you alter processing to push and pull?
"Truth and love are my law and worship. Form and conscience are my manifestation and guide. Nature and peace are my shelter and companions. Order is my attitude. Beauty and perfection are my attack."
I had similar results a couple of years ago with a box of 55. The prints always came out a little light as I processed for the negs. I underexposed a couple of sheets and, instead of a 25 count, I gave it 40 before pulling. Got a couple of really nice negs from the end of the box that way.