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Consolidation for Incremental retention can be disabled in the Reflect Defaults and Settings:
If consolidation is disabled and Incremental retention is applied to a backup set, Incremental backups are only deleted if to do so will not break the backup chain.
The number of incremental backups retained will always be at least the number specified by the Incremental retention rule.
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Example with Consolidation disabled:
Retain 3 Incremental backups
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