Quick pattern clarification

I’m working on my shrug
http://cache.lionbrand.com/patterns/50718.html
and I am doing the sleeve and it says
RIGHT SLEEVE
With larger needle (size 15), cast on 28 (30) sts.
Row 1 *K2, p2; rep from * across row; end k0 (2).
Row 2 P0 (2); k2, p2, rep from across row.
Cont in rib pat until piece measures 8 (10)”. Change to smaller needles.
Next row Knit, inc 1 st at each end of row.
Next row Purl.
Cont in St st and inc 1 st at each edge every 6th row two times—34 (36) sts. Work even until piece measures 16 (17) in.

when it says
Cont in St st and inc 1 st at each edge every 6th row two times—34 (36) sts. Work even until piece measures 16 (17) in
Am I measuring from the St st or from the ribbing???

Thanks!

:shrug: anyone??

You measure from the cast-on unless it says something different.

THANK YOU!!! :muah: