Android 5.1.1 API Level 22
Has your Nexus device received its update to Android 5.1? Good, get ready for a maintenance release. It appears that Google has a maintenance release for Android 5.1 ready to roll, with Android 5.1.1 showing up in the Android SDK manager.

The API level remains the same – API Level 22 – but updates to Revision 2. The update is present to update in your Android Studio if you’re a developer and while there’s no information in the description, it’s most likely in the testing phase by Googlers at the moment.
Android 5.1.1 in Android SDK

As Android Police point out, the revision was added on April 1st so it’s possible this is a subtle troll by Google – but it’s a subtle troll with 63MB worth of updates you can install so we’ll have to wait and see.

Update: We’ve checked our logs and turns out that we’ve seen at least a Nexus 6 rocking Android 5.1.1 (Build LMY47T) hitting the servers. Looks like it’s legit.