After some debugging on why our new board did not work when using our customization I found out that the Firefly-RK3399_Android7.1.1_170516 firmware does not operate on RK3399 boards produced after 2017-08-22.
The latest firmware releases do work on these boards and on the older boards as well.
Is there an overview of which hardware production dates require which minimum firmware release and what changed to the hardware ?