Mix yeast and water until entirely dissolved.
Shred or blend squash fine or rough, depends on your preference.
Add squash, sugar, salt, whole wheat flour, and oatmeal.
Slowly add wheat flour, but note that it's not supposed to be very firm. Squash is very watery, and this is what makes zucchini bread so amazing.
Let the dough rise on the kitchen table for 1 hour and 30 minutes. You can also let it rise overnight, by putting it in the fridge.
Put the vegan zucchini bread into a prewarmed oven at 325 degrees F (165 degrees C). Bake for 40-60 minutes. Let it cool for 30 minutes or more.