Firmware update 2.2.2.1?

My battery doorbell (wired) firmware updated to V2.2.2.1 on the 18th. There’s no entry in the ‘Firmware Records’ thread, so does anyone know what was included in the update?
One thing I have noticed is that when my battery is ‘fully’ charged, the power indicator changes from a plug to a battery meter temporarily until charging restarts.