 The 2010 Strategic Defence and Security Review reduced this number further and the submarines will put to sea in future with a reduced total of 40 warheads and a reduced missile load of 8 (from a maximum possible 16).The number of operationally available nuclear warheads is to be reduced 'from fewer than 160 to no more than 120 and the total UK nuclear weapon stockpile will number no more than 180.In January 2020, BBC announced it had commissioned a new thriller based on board a fictional "Vanguard"-class submarine.