There are several synonyms for the phrase "more on call" that can be used to express a sense of readiness or availability. Some examples include "on standby," "at the ready," "on alert," "prepared," and "available". These terms convey the idea that someone is ready to act or respond at a moment's notice. Other similar phrases might include "on duty," "on call," or "on hand." Whether you are discussing emergency situations, waiting for an important call, or simply being prepared for whatever might come your way, there are many ways to express the concept of being "more on call".