Help with mitten knitting pattern

I am working from a pattern that I got on Red Heart “Lacy Leaf Hat & Mittens” and I am stumped. In total the mitten is supposed to be 10" long. After the cuff, wrist shaping and an increase round it states to “Knit until piece measures 7” from beginning" then the next round would be “shape thumb”. My issue is I believe 7" is too long before starting the thumb shaping, I think it should not be more than 4" or 5". This is the first time I am knitting mittens. Any confirmation or suggestions?

Yes, it might be an error. It’s possible to have an extended wrist but not with such a tiny measurement left for the hand. You could measure the length you’d like to the thumb on your hand and place the thumb there, then knit the length of the hand to a comfortable length for you.