; and (ii) may not, except as provided in subparagraph (B), lease or acquire new vehicles or replace existing vehicles without prior approval from the Under Secretary for Management pursuant to paragraph (5)(B). (B) Exception regarding certain leasing and acquisitions If exigent circumstances warrant such, a component head may lease or acquire a new vehicle or replace an existing vehicle without prior approval from the Under Secretary for Management. If under such exigent circumstances a component head so leases, acquires, or replaces a vehicle, such component head shall provide to the Under Secretary an explanation of such circumstances. (3) Ongoing oversight (A) Quarterly monitoring In accordance with paragraph (4), the Under Secretary for Management shall collect, on a quarterly basis, information regarding component vehicle fleets, including information on fleet size, composition, cost, and vehicle utilization. (B) Automated information The Under Secretary for Management shall seek to achieve a capability to collect, on a quarterly basis, automated information regarding component vehicle fleets, including the number of trips, miles driven, hours and days used, and the associated costs of such mileage for leased vehicles. (C) Monitoring The Under Secretary for Management shall track and monitor component information provided pursuant to subparagraph (A) and, as appropriate, subparagraph (B), to ensure that component vehicle fleets are the optimal fleet size and cost effective. The Under Secretary shall use such information to inform the annual component fleet analyses referred to in paragraph (4). (4) Annual review of component fleet analyses (A) In general To determine the optimal fleet size and associated resources needed for each fiscal year beginning with fiscal year 2018, component heads shall annually submit to the Under Secretary for Management a vehicle allocation tool and fleet management plan using information described in paragraph (3)(A). Such tools and plans may be submitted in classified form if