What do I do with left over peach pulp? I was making peach preserves. I have 6 cups left, with no sugar in it. Thank you in advance

Freeze a bit of it in cube form and add to smoothies later; use some of it in unfrozen form in smoothies now. Also add to plain yogurt or ice cream.

Peach sorbet. Peach mousse - just sub in, e.g., a strawberry mousse recipe; or frozen mousse or semifreddo - if you do that, a good combo would be lining the pan/mold with crushed amaretti cookies.

Chutney or mostarda come to mind.

Swirl it into ice cream!

Echo the suggestions made below. You can also use it in a banana cake in place of some of the mashed bananas, or stir it in to a crumble or pie filling. Use to make a parfait, to top yogurt or ice cream, to stir into oatmeal. Make a mockktail or just stir into sparklin water. Mae a sweet and sour sauce for chicken, or even add to a homemade BBQ sauce.

Place in vodka, let sit for a week or 2. Impress your friends w summer cocktails.

You could freeze it in more manageable amounts. Maybe 2 cups? Then you could make ice cream, bellinis, ice pops.
I don't care for fruit in savory foods (a flaw of mine), but I'll bet there are recipes
on this site.

You can freeze it in ice cube trays and use a cube or two at a time for all sorts of things: cocktails, flavoring iced tea, melted with butter for a quick peach sauce.