Stitch Holder Mid Row?

How-to Questions
1

I’m currently knitting a neck piece, which has now become a curve and I need to place the central, flat part of the neck on a holder, with one side curving in that I have already knitted. However, I am mid row. I cannot knit the next few (17* see below) stitches to then place them on a holder, as this ruins my curve - the two parts have a significant height difference and a hole appears. I also can’t just slide them on a holder, as then my working yarn will be in the middle of the holder.

Completed: Next row knit 23, k2 tog, turn and work on these sts only for now
Next row - p2 tog, patt (knit 1, purl 1) to last 2 sts, knit 4
Cont to dec 1 st at neck edge in every row until 20 sts.
Work straight for 13 rows, ending on a wrong side row. Leave sts on a holder for now.

Issue:
Place next 17* sts on a holder for now, k2 tog, k to end.

How do I proceed? Eek!

2

One way or the other, you’re going to need to cut the yarn and work the second shoulder with a new strand of yarn. You can follow the directions, knit the left shoulder first, cut the yarn, place the center 17sts on a holder and then attach the new strand and follow the directions for the right shoulder.
The alternative is to knit across the left shoulder and the 17sts, then place them on a holder and work the right shoulder first. Don’t worry about differences in row height or curve. The neckband or collar will probably smooth all that out.