Not sure if you were already going to do this, but, might do well to topstitch the seam allowance down to get sharp edges
I’d say unpick (gah!) a large section opposite the zip to make is super easy to manipulate and accurate, and then sewup the unpicked seam, with final topstitch accessible from the open zipper ….in a perfect world, do as much of the fiddly top-stitching and seam-seal before joining the two sides, even joining the two sides/seam-work in stages, to avoid wrestling with tiny dark corners!
Not sure if you were already going to do this, but, might do well to topstitch the seam allowance down to get sharp edges
I’d say unpick (gah!) a large section opposite the zip to make is super easy to manipulate and accurate, and then sewup the unpicked seam, with final topstitch accessible from the open zipper ….in a perfect world, do as much of the fiddly top-stitching and seam-seal before joining the two sides, even joining the two sides/seam-work in stages, to avoid wrestling with tiny dark corners!