A current eventlog can never be older than seven days as it is constantly in use. However, backed-up eventlog can be older than seven days. Now, if you want to delete those eventlogs, then why do you back them up in the first place?

Alos, you cna specify how eventlogs overwriten the evententries, and you can also resize the eventlogsizes to have all events for a specific time period into them.

Thus, as other already repeatedly told you, please explain to us in detail what exactly you try to accomplish.
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There are two types of vessels, submarines and targets.