Round 36: Break one strand of CC1, add one strand of MC. *(K1, P1) to marker, SM, (K1, P1) 12 times, M1, (P1, K1) 13 times, M1 Pwise, (K1, P1) to marker, SM; repeat from *. 4 sts added; 272 sts.
Round 40: Break final strand of CC1, add one strand of MC.
Round 43: Break two strands of MC, add two strands of CC.
For Rounds 33-34, the first sentence of the instructions changed, so that the instructions for those two rounds now reads: Repeat rounds 5-6; 264 sts.
US 15 (10 mm) long circular needles (at least 40” or two sets for the long circumference), or size to obtain gauge