Was looking at doing this very same scenario… but with my M1 12.9” iPP… reckon I could just about get 50% of the purchase price of the 13” iPP and a keyboard selling my old one… and that is getting it through the education store as well… but it still leaves quiet a bit to find…Cost me AUD$2,578 from the Apple Education store. But I also sold my M2 iPad Pro, Magic Keyboard and Apple Pencil 2 for AUD$1650.
Funny thought though… the only reason I’d buy it is to maximise the trade in value on my M1… I’d be buying the m4 iPP just so I can get a great deal on my old M1 … thats a bit nuts isn’t it… or genius!!!!