Need help reading pattern sleeves too long

I don’t understand the first part about working in working cuff in reverse St St and every time I’ve done the sleeve with my calculations it’s come out way way too long. HELP the lady Kris who use to help me with knitting just died 2 months ago of breast cancer so I’m very lost with out her and her knitting ability

Note: Work in the cuff in reverse St st until there are 4 inc, enabling you to add 1 full rep.
Cast on 38 (38, 38, 38, 42, 42, 42) sts. Work as for Rows 1 and 2 of back ribbing, at the same time, work M1 at each end [every 4th row] 0 (0, 0, 0, 0, 0, 1) times, [every 6th row] 0 (0, 3, 9, 9, 10, 13) times, [every 8th row] 1 (8, 7, 3, 3, 3, 0) times, then [every 10th row] 6 (1, 0, 0, 0, 0, 0) times. (52, 56, 58, 62, 66, 68, 70 sts).
Continue to work even until sleeve measures 14 1/2 (15 3/4, 15 3/4, 16 3/4, 16 3/4, 16 3/4, 17 1/2) inches or desired length to underarm, ending with a WS row.

You adjust the length of the sleeve in the part that reads -
“Continue to work even until sleeve measures 14 1/2 (15 3/4, 15 3/4, 16 3/4, 16 3/4, 16 3/4, 17 1/2) inches or desired length to underarm, ending with a WS row.”

Measure a sweater who’s sleeve length is the right fit for you, from the wrist to underarm and that’s how long you should knit yours in this section.

Rev stockinette is when the purl side of stockinette st shows on the RS.