As cloud berry is widely used in several organizations for taking database backups in MS SQL Server.
By simple question is, even SQL Server doesn't support taking backup of a snapshot or those databases are restoring mode, offline etc. Even though this is trying to take backups and sending the report with warnings like the databases are in offline state or tried taking a backup of snapshot.

If the cloud berry team can enhance this as a feature for avoiding those types of invalid errors and I consider it will be a great change and alerts will be showing the happy smiley :) and everyday, this can produce a smile on the backup team as well :)