OSConfig Agent : how to update the agent itself when the GCE was deployed a long time ago

Hi,
We deployed GCE with osconfig a long time ago

But [1] says we need a version date later than 2021 04 27.
As we deployed hundreds of GCE, opening a session on every of them to enter
- sudo yum update google-osconfig-agent or
- googet update google-osconfig-agent
is not an option

Is there a way to automatically update the agent itself to the latest version ? By specifying a metadata key/value for instance ?

One may add commands to every startup script, but rebooting all of them is not an option too

Thanks

[1] https://cloud.google.com/compute/docs/manage-os/upgrade-vm-manager?_ga=2.77766036.-1613363622.1655387627#overview

Start with the linked VM Manager upgrade documentation and the agent update commands named in the report. Determine whether the repository has an entry point or documented mechanism for fleet-wide self-update; done means a supported, reproducible answer for updating existing GCE instances without per-VM sessions or reboots.

Written by the indexing model from the issue text.