On the Knit Picks website they say:
Many of you have asked about the potential for a 16″ cable to go with the Options needle tips. We donít offer 16″ cables for the interchangeable tips because the tips are too long to create a circle with such a short cable. We have expanded the sizes we offer in fixed 16″ circular needles. They have shorter tips to accommodate the shorter cable. You can find them on our Classic Circular Knitting Needles page. We thank you for your requests and your understanding!
I ordered 16" size 8 and size 6 circular needles, and like Nadja mine are backordered.
I did get my set of size 2 DPNs and "Dancing" sock yarn. I can't wait to start my first pair of socks.... just got to get up the courage to use the DPNs!