The Google Android 5.0 was just released few months ago that comes with major changes in interface, performance tweaking and system runtime. However, GSMArena shows that there is a new Android SDK Platform available in the latest Android SDK toolkit. The new Android SDK Platform was labelled as Android 5.1.1 which will be likely available in the public in next few weeks.
Since the older version of Lollipop faced severe memory leak issues, this Android update is likely to be the remedy for memory issue and other bug fixes. Nevertheless, most new Android-based smartphone is now running on Android 5.0 and only minimal amount of smartphone is eligible for Android 5.1 update. So it is unsure when will these update being rolled out to the public by each manufacturer.