Sadly, the contained kernel 4.4 is already EOL:
[2022-07-05T18:44:44+0200] ueberall_l@desktop01:/tmp% wget "https://github.com/radxa/debos-radxa/releases/download/20220701-0727/rockpi-s-ubuntu-focal-server-arm64-20220701-0851-gpt.img.xz"
[…]
[2022-07-05T18:45:47+0200] ueberall_l@desktop01:/tmp% xz -dv rockpi-s-ubuntu-focal-server-arm64-20220701-0851-gpt.img.xz
rockpi-s-ubuntu-focal-server-arm64-20220701-0851-gpt.img.xz (1/1)
100 % 140,6 MiB / 906,0 MiB = 0,155 92 MiB/s 0:09
[2022-07-05T18:45:59+0200] ueberall_l@desktop01:/tmp% fdisk -l ./rockpi-s-ubuntu-focal-server-arm64-20220701-0851-gpt.img
Disk ./rockpi-s-ubuntu-focal-server-arm64-20220701-0851-gpt.img: 905,101 MiB, 950000128 bytes,
1855469 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: gpt
Disk identifier: 34D6A485-96AB-4EAE-B781-BEA9FCBC918D
Device Start End Sectors Size Type
./rockpi-s-ubuntu-focal-server-arm64-20220701-0851-gpt.img1 32768 262143 229376 112M EFI System
./rockpi-s-ubuntu-focal-server-arm64-20220701-0851-gpt.img2 262144 1855435 1593292 778M Linux filesystem
[2022-07-05T18:46:07+0200] ueberall_l@desktop01:/tmp% mkdir ./rockpi-s-ubuntu-focal-server-arm64-20220701-0851-gpt
[2022-07-05T18:46:46+0200] ueberall_l@desktop01:/tmp% sudo mount -t auto -o loop,offset=$((262144*512)) ./rockpi-s-ubuntu-focal-server-arm64-20220701-0851-gpt.img ./rockpi-s-ubuntu-focal-server-arm64-20220701-0851-gpt
[sudo] password for ueberall_l:
[…]
[2022-07-05T18:49:16+0200] ueberall_l@desktop01:/tmp% dpkg-query -W --admindir=./rockpi-s-ubuntu-focal-server-arm64-20220701-0851-gpt/var/lib/dpkg >./rockpi-s-ubuntu-focal-server-arm64-20220701-0851-gpt.dpkg-query.txt
[2022-07-05T18:50:11+0200] ueberall_l@desktop01:/tmp% grep ^linux- ./rockpi-s-ubuntu-focal-server-arm64-20220701-0851-gpt.dpkg-query.txt
linux-4.4-rock-pi-s-latest:arm64 4.4.143-69-rockchip
linux-base 4.5ubuntu3
linux-firmware-image-4.4.143-69-rockchip-g8ccef796d27d:arm64 4.4.143-69-rockchip
linux-headers-4.4.143-69-rockchip-g8ccef796d27d:arm64 4.4.143-69-rockchip
linux-image-4.4.143-69-rockchip-g8ccef796d27d:arm64 4.4.143-69-rockchip
[2022-07-05T18:51:35+0200] ueberall_l@desktop01:/tmp%
Given that competing SBC have patches for the 5.15 kernel (and newer ones) which also slowly find their way upstream (if they have not been included already), I’m afraid that this is simply way too old. The system might run, but kernel 4.4 was published 6.5 years ago and isn’t tested against current software packages/applications (because it’s EOL) unless you manage to pay for it.
Please at least consider including a kernel that is not already EOL or won’t be EOL by the time the hardware will be available (IMHO, even kernel 4.9 will not really fit the bill, it’ll require kernel 4.14 or newer).
EDIT: As pointed out below by tkaiser, I downloaded the wrong image, so the rant is misplaced and does not apply to the ROCK5B (only to other/older models).