FCCS: Account in "Closing Balance" movement needs to translate at "Average Rate"

An Account exists outside the "Balance Sheet - Traditional Approach" hierarchy.
This account needs to be treated as a Revenue account, and needs to be translated at the "Average Rate" at "Closing Balance" movement.
In spite of assigning a "Translation Override" to this account, the account still translates at "Ending Rate" at "Closing Balance" movement.

How can this account be made to translate at the "Average Rate" at "Closing Balance" movement intersection?