Currently the ups-sidecar checks if a variant with the same name as the mobile client exists (to determine if it needs to create a new variant in UPS). This is unsafe because changing the name of the variant in UPS would make the sidecar no longer finding it.

The UID of a Variant can't be changed. When the ups-sidecar creates a new variant it should store it's definition along with the UID in the associated secret.

Whenever it's checking if a variant for a mobile client already exists, it should use the UID and no longer the name.