Sysbox doesn't seem to follow /etc/subuid when running a container

Hi all,

I'm running Sysbox 0.6.2 release with docker locally.
I'm currently trying to increase /etc/subuid subordinate range for sysbox, since I want to try to run Podman inside system container.

Linux version:

$ uname -a
Linux mdev 6.2.0-35-generic #35~22.04.1-Ubuntu SMP PREEMPT_DYNAMIC Fri Oct  6 10:23:26 UTC 2 x86_64 x86_64 x86_64 GNU/Linux

Output of /etc/subuid and /etc/subgid

$ cat /etc/subuid
mdev:100000:65539
sysbox:165539:100000
$ cat /etc/subgid
mdev:100000:65539
sysbox:165539:100000

When running docker container with following command:
$ docker run --runtime=sysbox-runc -it --rm --name=podman podman:v1

And executing inside the container:

podman@173ac4d31d89:/$ cat /proc/self/uid_map
         0     165539      65536

Is this expected or there's something on my part here which I didn't understand correctly how it works?
Should the given range inside container when cat /proc/self/uid_map be 100000 instead of 65536?
I've read docs and it says that with sysbox-mgr is possible to change this available range, but I couldn't find the right option for it.

Thanks!

Start with sysbox-mgr's handling of the host /etc/subuid and /etc/subgid ranges, then compare those values with the container's /proc/self/uid_map output. Determine whether the 65,536-ID mapping is expected and document or identify the configuration needed to use the requested range for Podman inside the container.