Hi all, about 6 weeks ago my HAOS stopped updating, as far as I can see without any local changes. As it was getting out of date I started with backups and a fresh install of Debian 13, KVM virt-manager and HAOS 16.2. I am on starlink so the internet is quick. I am running a Asus GT-AX6000 router.
That failed during the Preparing Home Assistant phase with

2025-11-01 07:18:20.296 ERROR (MainThread) [supervisor.docker.interface] Can't install ghcr.io/home-assistant/amd64-hassio-supervisor:2025.10.0: 500 Server Error for http+docker://localhost/v1.51/images/create?tag=2025.10.0&fromImage=ghcr.io%2Fhome-assistant%2Famd64-hassio-supervisor&platform=linux%2Famd64: Internal Server Error ("Get "https://ghcr.io/v2/": context deadline exceeded (Client.Timeout exceeded while awaiting headers)")

After trying all sorts at home with no results I got it to run at a neigbour's house and so HAOS is up and running apparently normally, but on returning home it will still not update, and gives one of two similar errors as below:-

Logger: homeassistant.components.websocket_api.http.connection
Source: components/websocket_api/commands.py:323
integration: Home Assistant WebSocket API (documentation, issues)
First occurred: 1:50:32 PM (2 occurrences)
Last logged: 1:55:12 PM

    [139943279508704] Error during service call to update.install: Error updating Grafana: Can't install ghcr.io/hassio-addons/grafana/amd64:12.0.0: 500 Server Error for http+docker://localhost/v1.51/images/create?tag=12.0.0&fromImage=ghcr.io%2Fhassio-addons%2Fgrafana%2Famd64&platform=linux%2Famd64: Internal Server Error ("Get "https://ghcr.io/v2/": context deadline exceeded (Client.Timeout exceeded while awaiting headers)")
    [139943279508704] Error during service call to update.install: Error updating Grafana: Can't install ghcr.io/hassio-addons/grafana/amd64:12.0.0: 500 Server Error for http+docker://localhost/v1.51/images/create?tag=12.0.0&fromImage=ghcr.io%2Fhassio-addons%2Fgrafana%2Famd64&platform=linux%2Famd64: Internal Server Error ("Get "https://ghcr.io/v2/": context deadline exceeded")

Looking through the logs I also see

2025-11-16 13:11:29.371 ERROR (MainThread) [supervisor.store] Could not reload repository 5c53de3b due to StoreGitError()
2025-11-16 13:11:29.371 ERROR (MainThread) [supervisor.store] Could not reload repository 29b65938 due to StoreGitError()
2025-11-16 13:11:29.371 ERROR (MainThread) [supervisor.store] Could not reload repository 77b2833f due to StoreGitError()
2025-11-16 13:11:29.371 ERROR (MainThread) [supervisor.store] Could not reload repository db21ed7f due to StoreGitError()

Thinking it must be the config on my router I configured an old Asus router to (I think) identical address (10.31.13.71 netmask 255.255.255.0) and dns servers (8.8.8.8, 1.1.1.1). That allowed the updates to complete. However on reverting to the newer router (which I need to do for other reasons) any new update fails as before.
I have since been nagging away at this for weeks now, and have changed every dns flag back and forth with no success.
I have also reverted the router firmware to one two releases earlier and even loaded the latest Asuswrt-Merlin firmware. Nothing seems to make a difference except using the older router which has never failed.
I assumed this was a dns issue, but the two routers appear identical and running nslookup ghcr.io on both gives the same ip address (4.237.22.32 as a Non-authoritative answer).
So now I am well past my network skill level, and need to troubleshoot this problem.
I assume this is some problem when trying to download the update or new version.
What can I do to find out what the new router is blocking? Can I manually try and download an update or is there a way to obtain a more detailed log?
Thanks in advance