Frustrated ... for the first (April) block, my "background 2" color is the same fabric I used as the "color 4" - IOW the color 4 is the leaf in section 9 and I used the same fabric for what I call the "stem" in section 7.
My "background 1" color is the same fabric in all my blocks, and I'm using the same fabric for the "leaf" in all the blocks as well - to tie them all in.
To my mind I would have preferred if they had used only one label called "background" and all other fabrics get a "color" label, then perhaps one called "border" for the side pieces.