Yep, most likely the purl round is the turning row for the them. I recently finished a Woobie (baby blanket buddy) that had a turning round that was k1, k2tog. That created a picot hem when it was folded. A purl row will just create a nice folded edge edge because of stockinettes natural tendency to fold over the purl.
I suggest you just start knitting it and take each instruction as it comes. It often makes more sense when you're knitting it than trying to figure it all out beforehand.