Now this is one I've never seen or heard of. Definitely sounds like the FW update failed. I would not remove the battery while its on. I would try the FW update again.
Sorry just realized you cannot try to update the FW again unless you can power off the battery. Very odd, I don't know what to suggest.
Just scanned through manuals and nothing about 2 LED's on like that.
This is what I would do ....so please think carefully before following my example.
I would remove the battery and place in a safe location and leave it to discharge down till the Shut Down occurs. This should occur at about 12.0 - 12.3V total. Once shut down, charge back up again - noting any strange light sequences etc.
Email dji and inform them of new light pattern,,,,this is one are that needs a update,,,no i cant say i seen or heard of this one either,,,whats it do with the 5 sec press test,,all light up,,,,i now very on edge with batt after using bad one myself and it caused complete shut down in flight from 71ft onto me house roof,,personaly i would not use it and i know they not cheap but cheaper than new drone,,,only wish mine happen under warranty