To build the current version kernel or images install a Debian 12 or LMDE6 VM on an x86_PC. Then do:
apt-get -y install git
git clone --depth=1 --branch=armbian-tv https://github.com/150balbes/build.git
cd build
./compile.sh BOARD=firefly-itx-3588j BRANCH=current BUILD_MINIMAL=no BUILD_DESKTOP=no BUILD_ONLY=u-boot,kernel,armbian-config,armbian-zsh,plymouth-theme-armbian,armbian-firmware,armbian-bsp KERNEL_CONFIGURE=yes
This will build just the 6.2 kernel and uboot. You will also still need to enable virtualization/KVM in the 6.2 kernel as it isn't selected.
To make a full Debian sid SD card image you do something like this, but I haven't tried it yet. You need to modify a config file in the subfolders to get normal Debian 12.
./compile.sh BOARD=firefly-itx-3588j BRANCH=current BUILD_MINIMAL=no BUILD_DESKTOP=yes BUILD_ONLY=default KERNEL_CONFIGURE=yes
There is ongoing work in the upstream Armbian to update the rockchip kernel for 6.5 and above, but currently it doesn't boot on 3588 boards.
https://github.com/armbian/build/pull/5657
After someone gets it booting on a more mainstream 3588 board then someone needs to be bribed to update the device tree files for the firefly ITX board. They apparently renamed the power related sections (among other things) in the new kernels. Going to the upcoming 6.7 rc if using the Collabora kernel there would be a (relatively) very small number of patches required to boot a 3588 board, but we still need to get device trees updated for all of them. If other boards get upstreamed I can maybe work on the DST stuff around Thanksgiving where hopefully they have some other boards working on 6.6 or 6.7 by then....