II spiked dramatically during the Helmand province campaign. Between July and September 2006, the theatre total for munitions deployed by British Harriers on planned operations and close air support to ground forces rose from 179 to 539, the majority being CRV-7 rockets. The Harrier IIs had also switched to 24-hour availability, having formerly operated mostly during the day. In January 2007, the Harrier GR9 began its first operational deployment at Kandahar, as part of the NATO International Security Assistance Force (ISAF); Harrier GR7s would be progressively withdrawn in favour of the newer Harrier GR9. Following five years of continuous operations in Afghanistan, the last of Britain's Harriers were withdrawn from the Afghan theatre in June 2009, having flown over 22,000 hours on 8,500 sorties, they were replaced by several RAF Tornado GR4s. Rundown In 2005, allegations emerged in Parliament that, following the transfer of servicing duties to RAF Cottesmore, the standard and quality of maintenance on the Harrier fleet had fallen dramatically; several airframes had been considerably damaged and one likely destroyed due to mistakes made, the time taken to perform the servicing had risen from 100 days to 155 days, and the cost per aircraft had also risen to more than ten times that of the prior arrangements performed by Defence Aviation Repair Agency (DARA). In 2006, the Sea Harrier was retired from Fleet Air Arm service and the Harrier GR7/9 fleet was tasked with the missions that it used to share with those aircraft. The former Sea Harrier squadron 800 Naval Air Squadron reformed with ex-RAF Harrier GR7/9s in April 2006 and joined by the re-formed 801 Naval Air Squadron in 2007. These later expanded and become the Naval Strike Wing. On 31 March 2010, No. 20 Squadron RAF, the Harrier Operational Conversion Unit (OCU), was disbanded; No. 4 Squadron also disbanded and reformed as No. 4 (Reserve) Squadron at RAF Wittering. All Harrier GR7 aircraft were retired by July 2010. The Harrier GR9 was expected to stay in service at least until 2018. However, on 19 October 2010 it was announced in the Strategic Defence and Security Review that the Harrier was to be retired by April 2011. In the long term, the F-35B Lightning II, would operate from the Navy's two new s. The decision to retire the Harrier was controversial, with some senior officers calling for the Panavia Tornado to be retired as an alternative;