Increasingly, teacher leaders are being asked to undertake administrative practices, particularly around instructional policy implementation. Yet little is known about this approach to teacher leadership in current educational contexts or how it may support teachers' work as boundary spanners between administration and faculty. This case study explores the duties and collegial interactions of two teacher-assistant principals (teacher-APs) and examines the challenges and resources activated through their professional endeavors. Findings suggest that the teacher-APs served as consiglieres, instructional leaders, and mediators between faculty and administration. This work positioned the participants as boundary spanners, who activated resources around policy alignment but also faced substantial challenges like ambiguity, overload, and instructional trade-offs.