"Rainbow in the Storm" Knitting Pattern (plus sizing)

Gauge: 20 stitches and 20 rows per 4” (10 cm) with fingering weight held double (st gauge is taken when stretched, row gauge is taken when relaxed).
Needles: (1) 24” (2) 40” circular needle in size needed to achieve gauge listed above (suggested size: US 10/6mm) plus (1) 24” size US 7/4.5 mm.
Materials Used: Hedgehog Fibres Skinny Singles held double (Fingering; 100% merino wool; 400 yds/100 g, or any other yarn that knits up to desired gauge). One strand MC held with one strand of 7 colors of the rainbow.
Yardage: Designer’s note: My estimations for this pattern came out to 1694(1782, 2024, 2057, 2145, 2178) yds MC + 100(100, 100, 110, 110, 110) yds per color of the rainbow. 2310(2398, 2640, 2750, 2838, 2948) total yards fingering weight yarn. Testers found that they used approximately 1190(1470, 1953, 1690, 1500,__) of their MC, so plan accordingly.
Other notions: Stitch markers, crochet hook/tapestry needle, scrap yarn/stitch holder, scissors.
Final measurements: 40(42, 44, 46, 48, 50)” / 102(107, 112, 117, 122, 127) cm chest circumference. Sweater is worn with 5”/13 cm-10”/25 cm of positive ease. Model is 34”/86 cm bust and wearing the 44”/112 cm size.