Build slack first.

1. Name one anchor

Every day has one activity whose completion makes the plan worthwhile. A second museum is never allowed to weaken the first.

2. Use bands

“Opening band,” “middle of day” and “later safe band” survive uncertainty better than fabricated exact times. Published hours are checked separately.

3. Separate transfer, entry and gallery time

Arrival at a district is not entry into a gallery. Security, orientation, toilets and mobility needs receive their own margin.

4. Make rest an activity

A proper break contains no attraction, commute or compulsory photo review. It occurs before attention has collapsed.

5. Add a decision gate

Before every optional second activity, the group asks about energy, time, transport and current access. “No” is a successful use of the plan.

6. Publish the fallback

Each route states what to remove first. This avoids compressing every remaining part into a worse day.