question about a pattern on circular needles

[skymy]

The pattern is worked on circular needles in an even number of stitches. Part of the pattern reads; rds 1-3: *K2, P2 to end of rnd. The 4th rnd: k2, p2, *repeat to last 4 stitches. End with k2, p1. Move marker 1 stitch to right and re-center round. I'm confused because I have the last purl stitch left and I don't know what is done with the stitch.

[suzeeq]

Move the stitch marker so it's after that p1, then start over with k2 on round 1 again. This is to offset the knits and purls for a spiral type rib.