Query on restricting override at assignment

Summary:

Content (please ensure you mask any confidential information): Currently, our system is set to "Allow Override at Assignment" under Position Synchronization Configuration in Workforce Structures -> Manage Enterprise HCM Information so HR can override the other relevant fields like department, job or grade. However, we are planning to restrict override so the fields should be synced based on the position.

With this new change, I want to confirm if the existing user assignments will be automatically synced based on the position once we run the "Synchronize Person Assignments" job.

When we tested setting this configuration, it says that the effective date can be the current date or future date. It means that it will consider only assignment records which are effective after this change effective date is my understanding. Is that correct?