How often are lore stories released?

There was a discussion thread about Zed's new lore where a rioter confirmed that there was a story being worked on that surrounds Shen, Zed, and Akali (also Jhin I believe). I was just curious as to maybe when we can expect it to be revealed? I don't know if they're allowed to answer questions like this, but if so could we get a general idea of when? I'm just really excited for their lore, since they are some of my favorite champions.