If you hide the left sidebar, and then print, then it is aligned correctly. Each H1 is on a separate page, which is certainly a choice, but on cursory inspection, it would seem as if all the content is there.

Ah, good catch. At work so didn't play with it too much.

Tbh, would probably still recommend rendering it with pandoc because the h1's being split that way does annoy me, but at least it gets the content right.