A method of generating a control schedule for a wind turbine is provided, the control schedule indicating how the turbine maximum power level varies over time, the method comprising: receiving input indicative of a target minimum wind turbine lifetime; determining a value indicative of the current remaining fatigue lifetime of the wind turbine or one or more turbine components, based on measured wind turbine site and/or operating data; and varying a parameter of an initial predefined control schedule that specifies how the turbine maximum power level varies over time. The parameter is varied by: (i) adjusting the parameter of the initial predefined control schedule; (ii) estimating the future fatigue lifetime consumed by the wind turbine or the one or more turbine components, over the duration of the varied control schedule, based upon the varied control schedule; and (iii) repeating steps (i) and (ii) until the estimated future fatigue lifetime consumed by the wind turbine or each of the one or more turbine components is sufficient to allow the target minimum wind turbine life to be reached.