APrioritizeItemsOver

Optional. This setting is equivalent to the size that you select for Start With Items Larger Than on the Archiving Rules tab of the Exchange Mailbox Policy dialog box.

This setting is for the filters that are associated with the mailbox, and it does not apply to other folders.

If you specify APrioritizeItemsOver, you must also set values for all the following:

UseInactivityPeriod (must be set to true)
APrioritizeLargeItems
ALargeItemThresholdUnits
ALargeItemThresholdPeriod

Possible values:

An integer that specifies the size of items in KB to which you want to give priority