I made this dress numerous times last summer including the one above, however, I wanted to wear this one now and it's a little too early in the year to go sleeveless. I used the sleeve from V8511 and it fit perfectly:
The dropped shoulder on V1250 is virtually the same as the pattern above:
I did find the sleeve very wide and I started narrowing it from one inch under the arm tapering down to a mark I made 2" in from the wrist seam. That slimmed the sleeve and it is tight enough to stay pushed up when I what that look. I drafted a sleeve for V1250 last year but this one fits and feels much better. Try it...it's a good fit!