Healthcare systems are limited resource environments where scarce capacity is often reserved for the most critical/urgent patients. However, there has been a growing interest in the use of proactive care when less urgent patients may become urgent while waiting. On one hand, providing care for patients when they are less urgent could mean that fewer resources are needed to return them to a healthy, stable state. On the other hand, utilizing limited capacity for patients who may never need that level of care in the future takes the capacity away from the other more urgent patients who need it now. To understand this tension, we propose a queueing model with two customer classes: moderate and urgent, and customers can transition from the moderate class to the urgent class while waiting. We characterize how moderate and urgent customers should be prioritized for service when proactive service for moderate customers is an option. Our focus is on the transient setting, where a demand surge pushes the system away from its normal state of operation. The goal is to cope with the surge in a cost-effective way. In this context, we demonstrate how optimal control theory can be applied to derive structural insights into the optimal scheduling policy.  This is based on joint work with Carri Chan and Yue Hu.