You pass Driver CPC part 2 on 30 May 2026 but delay Driver CPC part 4. What is the key timing rule?

1. The part 2 pass letter is valid for 2 years, so part 4 must be passed by 30 May 2028 or part 2 must be retaken
2. The part 2 result never expires
3. Part 4 must be passed within 3 clear working days
4. Part 2 becomes valid only after part 1 is passed