Before I take this new battery back to the retailer, a quick check to see if anyone has any ideas.

1. New battery put on charger (only lights one segment at first, but goes to 4 in fair time)
2. Put into P3A and starts the battery firmware update
3. Continues to flash R/G on the camera led
4. Two middle leds on battery remain illuminated
5. Nothing new happens bar buzzing etc. from P3
6. Remove battery (get the shits with the buzzing afet 10 minutes) and two middle led still stay lit and will not turn off

Good suggestions warmly received.

Being something of an expert on fixing DJI programming  issues I have resolved this.

Take out sd card, re-format and put image back onto card. Then put new battery in and it worked. WTF didn't it work with the image already on the card and which updated battery and aircraft OK at the weekend?

Seriously, DJI have a serious programming issue. Why? The Chinese are the major hackers in the internet world these days, but DJI can't they get some consistency in their firmware upgrades?