Benefit plan changing from 2 tier to 4 tier - will employees move automatically into the new tier?

This is regarding Benefit Rates. Our Dental plan rates are changing from a 2-tier structure (employee / family) to a 4-tier structure (employee / EE+SP / EE+CH / Family).  If an employee makes no changes during annual enrollment, will PeopleSoft be able to accurately move them into the new tier automatically?  For example, if an employee is only covering their Spouse, currently, they have Family coverage.  But in 2022, when we move to the 4-tier rates, they will move to Employee+Spouse coverage.  How does this happen behind the scenes without requiring the employee to update PS?