Direct communication with the HR resource is the most effective approach to understand their concerns regarding the project plan. This aligns with conflict resolution strategies that emphasize direct engagement and problem-solving as key methods for addressing disagreements and misunderstandings in project management contexts12. By speaking directly, the project manager can gather firsthand information, clarify any misconceptions, and work collaboratively with the HR resource to address any issues, ensuring that the project plan aligns with HR requirements and constraints.
References: = This approach is supported by PMI's guidelines on conflict resolution, which suggest that direct conversation is often the best first step in resolving conflicts, as it allows for immediate clarification and the opportunity to address concerns in a constructive manner123.