Stolen sector clock

[MPN11]

How do they manage an 8 day clock? What are the SOPs?

1. Someone winds it every Sunday [but if there's a raid on, someone might forget?]
2. Aged Retainer comes in once a week to wind it [what happens if he gets sick, or dies?]
3. Duty Airman issued with key, winding for the use of [what happens if he's sick, hungover or forgetful?]

On these thin threads hung the survival of Great Britain.