; and (2) is in a grade below E-6. 615. Determination of cold weather location for purposes of special duty pay For purposes of special duty pay under section 352 of title 37, United States Code, the Secretary concerned shall determine that a duty station is a cold weather location if, at such duty station, the temperature is expected to drop below -20 °F according to the 2012 Plant Hardiness Zone Map published by the Agricultural Research Service of the Department of Agriculture. 616. Feasibility study regarding assignment incentive pay for members of the Air Force assigned to remotely piloted aircraft Not later than 180 days after the date of enactment of this Act, the Secretary of the Air Force shall submit to the Committees on Armed Services of the Senate and House of Representatives a report on the feasibility and advisability of paying assignment incentive pay under section 307a of title 37, United States Code, to members of the Air Force assigned to remotely piloted aircraft, including at Creech Air Force Base. The study shall include— (1) an assessment of the financial stress experienced by such members, especially junior members with families, associated with— (A) the daily commute to and from the duty station; (B) the unique demands of the mission to remotely pilot aircraft; and (C) limited access to essential services, including child care, housing, and readily accessible health care