I can't answer the Corry questions, but if your orders say accompanied you wouldn't be eligible for family separation pay and your BAH would be based on Corry rates. If your orders say unaccompanied you would be eligible for family separation pay and your BAH would be based on your dependents' location (Mississippi).
EDIT: Some references
JTR
Chapter 10 Part E Section 5
1. A member with a dependent who serves an unaccompanied/dependent restricted tour (see DoDI 1315.18)
OCONUS or unusually arduous sea duty outside the U.S. is authorized a dependent’s location-based with dependent
housing allowance, or an old PDS-based with-dependent housing allowance if the dependent
remained in the residence shared with the member before PCS, did not relocate, and is not in Gov’t Qtrs. See
Table 10E-6 for specific situation-based rate information.
Chapter 10 Part E Section 8
A. General. The FSH allowance is based upon a separation resulting from military orders and not the personal
choice of the member and/or dependents. It is payable to a member with dependents for added housing expenses
resulting from separation from the dependents when a member is assigned to an OCONUS PDS, or to a PDS in
CONUS to which concurrent travel has been denied. General conditions are:
1. Dependent transportation to the PDS is not authorized at Gov’t expense under 37 USC ยง406;
2. Dependents do not reside in the PDS vicinity; and
3. Gov’t Qtrs are not available for assignment to the member.