Tadghthepom -
I'm just chiming in here to say that I'm a huge believer in thinking about page turns and layout as you write and revise a PB. That said, unless you're an author/illustrator or self-publishing, once you have your story within reasonable boundaries with enough scene variety and a payoff for every page turn to fill a 32-page PB, I wouldn't worry too much about hitting the page-count number exactly.
PB designers at the publishing houses do a magnificent job of laying out the book. Often, illustration backstory is shown on the title page. Or the story might extend onto the endpapers. I think it's always wise to consider PB structure and layout to make sure you have a viable PB, but then let it go, don't overthink it and get it into hands of a wonderful editor!
Good luck!
Jean