It is possible to use Mediaset properties (Append period and Overwrite Protection Period) for the B2D to set it in such a way that backups will be overwritten every 'X' number of days or weeks.
But it is not possible to delete just the incremental backups in one B2D if such a B2D contains full, incremental and differential backups. In that case i would suggest you to create different B2D for each kind of job. One B2D for incremental, one for full..etc.
And overwrite the B2D incremental using Overwrite Protection Period.
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