You can update your device manually running Android Lollipop.
To check your version number or get the latest system update for a Nexus or Google Play edition phone, first go to Settings > System > About phone or About tablet. Then look for these labels:
If you don’t have a Nexus or Google Play edition phone or tablet and are running Android 5.0 on some other device, some details of the system as described in this book may vary.