1-8
: 1s+2s+3s Adv+Ret; 1s dance in & cast (2s step up)
9-16
: 2s+1s+3s Adv+Ret; 1s turn RH (birl) to finish facing 1st corners
17-32
: 1s dance Corner Chain with 1st & 2nd corners:

: 1s change pl RH with 1st crnrs, 1st crnrs turn LH in centre & return to
  places giving RH to 1s who turn LH in centre to face 2nd crnrs

: 1s change places RH with 2nd crnrs, 2nd crnrs turn LH in centre & return
  to places giving RH to 1s & 1s end with a 1/2 turn LH to 2nd place own
  sides. End 2 1 3