Can the future hires incorrectly get assigned to the prior year compensation plan?

No, the automatic role assignment functionality will use the participant's detail attributes dates to match with the assignment rules date range.

For example, if the new hire for 2025 has the participant attribute detail record starting only in 2025, then it won’t match the rule that would assign the role or the compensation plan for 2024. The role assignment will start in 2025.