Notably, Google hadn't released Android 5.0.1 factory image for the Nexus 7 (2012), while it did for Nexus 7 (2013).
The official changelog provided by Google from LRX22C cuild to LRX22G build of the Nexus 7 Wi-Fi, essentially works on performance and deals with issues like tune delivery and batching of alarms, bad alarm delivery, storage, fstrim boot time and more. Notably, the factory image listing page still does not feature Lollipop factory images for the Nexus 7 (2012) 3G tablets - stopping at Android 4.4.4 KitKat.
The updated build of Android 5.0.1 Lollipop comes with build number LRX22C and improves upon stability, apart from fixes for bugs about which users have been complaining for quite some time."This software update will upgrade your Nexus 5/ Nexus 4 to Android 5.0.1, which improves performance and stability and fixes bugs. Downloading via Wi-Fi is recommended. Downloading over a mobile network or while roaming may cause additional changes," stated the OTA update description.