Accidently marked all clients as “Scheduled backup”

Today I’ve marked all clients as “Scheduled backup” (by checkmarking the “Scheduled backup” box clients not in the group but under “clients”).

The backup jobs are already running, NSR auditlog is not activated, 99% of the clients are assigned to a group, a lot of clients are existing several times (e.g. with different retentions or different schedules) and altogether about 750 clients are configured.

The server release is NetWorker 8.2.4.4.

Questions: How can I check for clients have now the “Scheduled backup” selected, but haven’t had before? E.g. is there a way to select all clients which didn’t run between yesterday and first of April?