I have created a PR for this
https://github.com/vyos/vyos-1x/pull/5561

This behaviour was observed on our current production version from January 2026.
I have tried it on the rolling version from the 7th October but i cannot get this version to work because it is affected by the interface renaming bug (T9291), so the WWAN interface will not come up at all.
I guess we have to wait until the bug is fixed before we can test if the bug we discovered is still applicable.

This PR has been merged

I have looked at how it used to work at it appears it still had the same issue but without the error.

I have setup a very basic container and investigated how the environment variables are actually passed and noticed that they are not being quoted correctly. So
"00 30 03 * * *" end up as just 00