I have just read in the DJI forum that the Air has a new Fimware update as at 28 Feb 19
•Date : 2019.02.28
•Aircraft Firmware : v01.00.0560
•Remote Controller Firmware : v01.00.0200
•DJI GO 4 App iOS : v4.3.12
•DJI GO 4 App Android : v4.3.12
•Aircraft: Optimized battery level algorithm.