There is an error on the shading on the chart.
The Lace pattern is only 7 sts wide but the gray shading also includes 2 purl sts (RS rows) at the LHS of this area. So when working the transition into the rib pattern at the yoke rep only the first 7 sts of the gray shading on the chart.

Sizes:
XS (S, M, L, 1X, 2X); 31 1/2 - 47” / 80 -119.5cm