I appreciate your help and time a lot. Thank you very much for helping this far. I will wait for more feedback from Radxa team.
The logs enumerated with time (0-7 secs) start 13 seconds after powering the board. That’s why it takes 20 seconds in case of Linux 4.4 in order to reach login screen.
I also think that maybe system looks for SD/eMMC image before NVME, but as I have read in the forum SPI flash has highest priority (and I believe SPI flash is responsible for NVME), so that is kind of strange.
By the way, my NVME is not connected through USB3, but directly through M.2. slot.
Anyway, thanks again, I will wait for Radxa’s response.