You know, I'm aware it's a mystery quilt and all, but I do wish Bonnie had said, "On those square in a square blocks, press all the seams to the inside on the first set and to the outside on the second. Don't ask why. You'll thank me later."
But of course, not knowing how the blocks were to be assembled, I didn't. I pressed the seam allowances to the inside on the first two diagonal sides and to the outside on the second two, to distribute the bulkiness at the points. Just a habit of mine. It works fine unless of course two like blocks are intersecting there. In that case I plan my pressing so that the intersecting blocks lock together at the opposing seam allowances.
Too late now.
But maybe not for you. If you've looked ahead at the design but haven't finished all your square in a square blocks, you can address the intersecting points issue by pressing all your seam allowances so that they are never all lying on one side of the points. Just thought you'd like to know.