An ESO Plus membership will not grant you access to The Elder Scroll Online: Morrowind content. As this is an entirely new Chapter of ESO, you'll need to purchase one of the five editions. If you already own ESO, though, you can purchase the Morrowind Upgrade or the Morrowind Collector's Edition Upgrade directly from online stores (The Elder Scrolls Online Store, Steam Store, Xbox Store, or PlayStation Store).
Okay... I've been expecting this

But... we were promised 4 DLC (or "major updates") / year ... are we still getting a DLC or a major update in Q2/2017, separate from "Morrowind" and included with ESO+ or purchasable in crowns - or even free, like Homestead ?