Using yarn held double (so half the yardage)
Still lighter than the DK called for in the pattern, but works well, light and with a nice drape. I usually don’t like knitted cotton because it feels heavy, but this one is great - it weighs only 120g!

The lace pattern is on both RS and WS, with awkward P2tbl.
With dec at the start of each row, you have to work out with what pattern stitch to start, to ensure the decreases do not cause the pattern to go out of sync with the preceding row.

21/07 - back done. I’m blocking a bit over the stated measurements, assuming it will shrink back a bit after unpinning. It was kind of tricky to knit up to the required length: depending on how I laid it out flat to measure it while knitting I got a difference of almost 2 inches because of the lace.
I cast on for the smallest size, but stopped the decreases as per the 2d size ‘cause I was afraid it might be a bit tight otherwise. This means the decreases stop a bit sooner than in the pattern schematics.
I also added a couple of inches to the length, I think it would look nice a bit more tunic length.
I think (hope) it will still work out!

For each side I very conveniently used all of 1 of the 1/5 cones remaining from the Après Surf hoodie, held double with yarn from a fresh cone.