Updating firmware in the Evnex charger

[smbunn]

My Evnex supplier has told me I am a year out of date with firmware and sent a link to the latest firmware.
https://s3.ap-southeast-2.amazonaws.com/firmware.evnex.io/ChargePoint_1.2.9.89da3d7_HWV0-1_Release.dfu

He also said that this is easiest updated via a firmware update command in my OCPP installation. Can this be done in this OCPP implementation and if so, how please?

[dreimer1986]

It worked twice on my EVBOX, so... it should. Here what I did:
#221 (comment)