I have got a kind of special BPI-R3, @sinovoip : Have a close look on the marking of the two flash chips: it is the same, W25Q256JVEIQ. So two times NOR flash, but unfortunately no NAND flash.
This is very sad, I was really happy to have found a powerful router board that has NAND flash and an eMMC flash to evaluate running containers on it. Planed storing OpenWrt on the NAND flash while using the eMMC to store the container images and so on. But now I have one without any NAND flash
It was also really annoying to find out, why flashing to the NAND flash did not work at all, always just flashed to NOR flash regardless of how the jumpers was set.