Normally, with an event from supercell, it means an update is coming soon. One gem boosts, wizzard stuff, etc, all those events eventually lead upto the update by ending them with the next update. So my guess, sneak peeks by the next week, and this event will last for one to three weeks. If Im correct, most updates have a boost or small event so the next update is most likely Febuary. Just a prediction Im sure everyone has already made, but just putting it out there Incase someone hasn't.