Why can't I update my Airport Express?

Good evening all!

I just noticed that my Airport Express (2nd Gen I believe, which I also use as an extender) quit working on me yesterday, as I noticed a significant decrease in wifi strength in the far reaches of the house. I opened up AirPort Utility and see that my AirPort Express has the flashing amber light and a red "1" badge next to it. After a quick search, it looks like the Express is in need of an update.

Here's the problem...I cannot find a button/option to update the AirPort Express. When I click the base station, it allows me into the "edit" area, but no where can I find an option to update.

FYI...I'm running OS X Yosemite on my iMac and the Airport Express is running version 7.6.4.

So, how do I update the base station?