Hi Dana! That's a very pretty dress and looks perfect for the Alice & Wonderland themed fundraiser! That shade of blue is beautiful.
I purchased a skirt from Chicwish in 2017, when I fell in love with the Jasmine Night Floral Skirt (pic posted below) featured by Jean Wang from Extra Petite. I am not petite, as I am 5' 6" tall. I ordered the large as I am usually a US size 8 which seems to still translate to a large on the Chicwish size conversion chart. The fit was (and still is) perfect. I still have the skirt and I still enjoy wearing it. It is 100% polyester so I have thrown it in the wash with other dark clothes and the colour didn't fade, the stitching is still intact with no fraying of the hem, and the zipper glides well.
When I ordered it, I didn't need it for a specific date. I don't remember how long it took, but I also don't remember any issues with taking too long either. (I live in Toronto, Ontario, Canada.)
If you look at Jean's post that I linked above, she has a review of Chicwish within the skirt review, some tips for choosing an item, and her experience shopping there. As Carol mentioned, shipping can take a few weeks to arrive.
I see that the dress you would like to order is 100% cotton with a fully lined bodice. That sounds promising! I see that it also says to hand wash cold. I might be wary of that because of shrinkage.
If you do decide to order the dress, I'd like to know about your experience and your dress review. Good luck!