Update on Splashes?

So, we all know a few months ago some of our favorite champs got splash art updates. I for one was thrilled to see all the new art and I can't help but wonder when new ones will come out. Now that Ryze and Ashe are being updated, you can expect them to be given new art along with it. Just wondering when these new splashes will come and which patch they'd be mentioned on. ^^