afaik LND in Umbrel automatically does an encrypted channel backup to the Umbrel servers, so the funds can be recovered in case of a failure without worrying about a backup myself.
Question: Does Core Lightning in Umbrel the same, also backing up the channels to the Umbrel servers?
It appears Elements are working on similar features right now → Add option for channel backup and recovery · Issue #21 · ElementsProject/cln-application · GitHub
As I understand, the recovery for process for Core is fairly different from LND, and at the moment does not include automatic back-ups on the Umbrel side.
You will need to do it manually from the command line following the above.