# make sure that your system is up-to-date and has kernel 6.5 installed

sudo umount /boot
sudo cryptsetup luksOpen /dev/nvme0n1 reform_crypt
sudo mount /dev/mapper/reformvg-root /mnt

check /mnt/etc/fstab:
/dev/reformvg/root / auto errors=remount-ro 0 1
/dev/mmcblk0p1 /boot auto errors=remount-ro 0 1 # this is now pointing to SD and not eMMC!
UUID=56fdfac2-44b8-4616-834e-2b61d1c1ab0a none swap sw 0 0

sudo mount /dev/mmcblk0p1 /mnt/boot/
sudo mount -o bind /dev /mnt/dev/
sudo mount -t sysfs sys /mnt/sys/
sudo mount -t proc proc /mnt/proc/
sudo cp /etc/resolv.conf /mnt/etc/resolv.conf
sudo rm /mnt/etc/flash-kernel/machine

sudo chroot /mnt apt-get install --reinstall linux-image-6.5.0-0.deb12.4-reform2-arm64

check:
$ file /mnt/boot/dtb
/mnt/boot/dtb: symbolic link to dtbs/6.5.0-0.deb12.4-reform2-arm64/amlogic/meson-g12b-bananapi-cm4-mnt-reform2.dtb

$ ls -lha /mnt/boot/
total 62M
drwxr-xr-x  5 root root 1.0K Dec 28 19:05 .
drwxr-xr-x 19 root root 4.0K Dec 28 19:03 ..
-rw-r--r--  1 root root 4.9K Dec 28 19:05 boot.scr
-rw-r--r--  1 root root 4.9K Dec 28 19:04 boot.scr.bak
-rw-r--r--  1 root root 297K Dec 24 15:42 config-6.5.0-0.deb12.4-reform2-arm64
lrwxrwxrwx  1 root root   82 Dec 28 19:05 dtb -> dtbs/6.5.0-0.deb12.4-reform2-arm64/amlogic/meson-g12b-bananapi-cm4-mnt-reform2.dtb
lrwxrwxrwx  1 root root   82 Dec 28 19:05 dtb-6.5.0-0.deb12.4-reform2-arm64 -> dtbs/6.5.0-0.deb12.4-reform2-arm64/amlogic/meson-g12b-bananapi-cm4-mnt-reform2.dtb
drwxr-xr-x  3 root root 1.0K Oct 23 13:50 dtbs
drwxr-xr-x  2 root root 1.0K Dec 28 19:05 extlinux
-rw-r--r--  1 root root 1.5M Oct 23 13:50 flash.bin
-rw-r--r--  1 root root  32M Dec 28 19:05 initrd.img-6.5.0-0.deb12.4-reform2-arm64
drwx------  2 root root  16K Oct 23 13:50 lost+found
-rw-r--r--  1 root root   83 Dec 24 15:42 System.map-6.5.0-0.deb12.4-reform2-arm64
-rw-r--r--  1 root root  29M Dec 24 15:42 vmlinuz-6.5.0-0.deb12.4-reform2-arm64

sudo umount /mnt/proc
sudo umount /mnt/sys
sudo umount /mnt/dev
sudo umount /mnt/boot
sudo umount /mnt
sudo vgchange -an reformvg
sudo cryptsetup luksClose reform_crypt