1080p with Custom Windows 10 IoT Core FFU for the Dragonboard410c

I have read that the dragonboard410c only has a resolution of 720p by default. To expand the resolution to 1080p, a new ffu file must be created which contains the current BSP files (db410c_bsp_mar2019.zip) from the dragonboard410c. I created this according to the instructions with the Windows build 17763 and it does not work. The picture on the screen is not displayed correctly. I use a screen from waveshare (10.1inch HDMI LCD (B)). Does someone have an idea how I can solve the problem?