A: Since this hat is knit flat and seamed at the end the ribbing is reversed every other row. This makes it so that regardless of which side you are working, the knit stitches are always knit and the purl stitches are always purled. This is what keeps the ribbed pattern consistent. When you finish the hat and get it seamed up the section of 4 purl stitches that you pointed out will not look like 4 purls. Seaming uses up an average of 2 stitches (one on each side) so when the hat is finished it will look like a P2 just like the rest of the ribbing. You may notice a ridge/line and those stitches may not look perfect but that's the nature of seaming! I recommend using the mattress stitch since it creates a clean seam line and is nearly invisible with practice.