The answer is; 9.00 PM
Water gains heat slowly and loses heat slowly because of its high specific heat capacity. Therefore during the day, land takes shorter time to heat up from the sun, than water bodies. This is why breezes during the day blow onshore (sea breeze).
However, when the sun sets, land begin to lose heat rapidly than water bodies. Therefore warm air above water bodies is less dense and rises and replaced by denser air from land. Breeze, therefore, blows offshore (land breeze).