How does Worksheet Update End Date work for Secondary Managed Plans?

In the Plan Access, we have Worksheet Update End Date of 14/04/2025.

For some secondary managers, they have No Updates Allowed on 14/04/2025.

But for some, they still have Updates Allowed on 14/04/2025.

Updating the date to 15/04/2025 results to both of them having Updates Allowed.

How exactly does the access work in these scenarios?

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