FG, the CZTE is determined by Presidential Executive Order, and not by OSD or the Services. CZTE and IDP have never been linked. The only exception is in the Kosovo region where a Public Law (Congressional action) has authorized CZTE for it being a qualified hazardous duty area. https://www.irs.gov/uac/Combat-Zones
So, barring any new PEOs, the "Arabian Peninsula Areas, beginning Jan. 17, 1991 -- the Persian Gulf, Red Sea, Gulf of Oman, the part of the Arabian Sea north of 10° North latitude and west of 68° East longitude, the Gulf of Aden, and the countries of Bahrain, Iraq, Kuwait, Oman, Qatar, Saudi Arabia and the United Arab Emirates" will continue to provide CZTE status.