First up, Yesenia's Upcoming Vector Demo will still be released June 2nd. I talked about it last update. She will record herself vectoring an image of kid!sapphire I uploaded to our tumblr.
As for Sapphire's concept art, I released her first image last month, and this month I finished her second pose, ready to be vectored by Yesenia. I'll release it along with all 3 concept images I've done, pre-vectorization, when they are complete.