Highway Code Rule 238
You MUST NOT wait or park on yellow lines during the times of operation shown on nearby time plates (or zone entry signs if in a Controlled Parking Zone) – see ‘Traffic signs’ and ‘Road markings’. Double yellow lines indicate a prohibition of waiting at any time even if there are no upright signs. You MUST NOT wait or park, or stop to set down and pick up passengers, on school entrance markings (see ‘Road markings’) when upright signs indicate a prohibition of stopping.