Well, you've got a point there. I sort jumped the gun that they'd allow it since I added a piece clothing to my order before, but obviously changing sculpts would be a bit different. I really hope they allow it though, because I really feel like Ryuna would be more versitile with posing and clothing/wig styles.
Not to mention, I had two characters thought up for Lia, but only one really fit her. Meanwhile, Ryuna would be able to take both rather easily.