The update worked for me. I had drained 12v battery every 4-5 days. I suspected the new 3G modem and turned off the overnight charging station Carwings update. The battery issue went away. I learned of update and took Leaf into shop. Tech initially questioned my analysis until I used Nissan app to remotely check battery status while he had meters connected. The 12v current spiked high and stayed high through the update. If the circuit remained open for some reason, I would have a dead 12v waiting for me in AM. He made the software change. No recurrence of problem with daily overnight status updates and frequent remote checks.
2013 SL Blue Ocean
Bought used, March 2015 12,764 miles
4th bar drop 56 month, 20,200 miles, AHr at 42.1
Appears fully loaded
Condo home, Using public charge except in emergency
Dallas, TX downtown, shaded non-temp controlled garage