Debian 12 Bookworm and 11 Bullseye for Libre Computer Boards

Somehow I did download an Debian stretch image frome here somewhere? But now only this entry remain? Weird. I tried this minimal image, but it is not sufficent for my useage needs. There is no dbus, no audio drivers no hdmi drivers, nothing. For a server this would be ok, but not for my needs (network device that transfers audio to HDMI) The images in my database are:
libre-computer-aml-s905x-cc-debian-stretch-xfce-mali-4.19.55±2019-06-24.zip.
libre-computer-aml-s905x-cc-debian-stretch-headless-4.19.55±2019-06-24.zip

Where did they go? Where to find updates? I would like to go to the new kernel…

This is because the current image causes HDMI to stutter for 0,5 secs every 8 seconds? I have read somewhere, this issue is resolved in Debian Bullseye. But searching here results in this dead end… Did you all drop Debian support? I do not understand this, since Debian stands for free software, as in freedom, and your hardware does too, right?