In Ireland state funded support services provide Continuing Professional Development for teachers and school leaders. These services are staffed with teachers seconded from their schools on an annual basis for a maximum of five years. This study investigated the learning and experience of teachers seconded to a national support service, the Professional Development Service for Teachers and how this influences their post-secondment career. It employed qualitative interviews exploring this from the perspective of teachers previously seconded to the PDST. The theoretical framework was rooted in the field of career dynamics setting out three stages (Entry, Experience, Exit) navigated by teachers from entering the service through to their departure. This article focusses primarily on the study findings for the Experience stage while necessarily providing relevant insights from the Entry stage. Attention is drawn to the distinct role and identities of teachers seconded as 'Continuing Teacher Educators'. Findings show that the learning they acquire is extensive while also revealing tensions in managing hybrid identities as teachers/teacher educators. Most notable are precarious tensions between the catalytic impact of secondment and the uncertain nature of its tenure. For most, this eventuates in a premature departure from the service to other careers, paradoxically having reached proficiency as teacher educators.