Blended Synchronous Learning (BSL) refers to when students located in physical classrooms learn together with peers who attend remotely, via networked digital technologies. The COVID-19 pandemic, along with ambitions to increase flexibility in learning delivery mode for students, has led to the increased implementation of BSL in tertiary education. The current evidence-base around BSL provides important principles for its use, but relatively little research has examined the experiences of teaching staff in depth. This article uses a self-study methodology to explore educators' experiences of BSL implementation in a post-graduate Initial Teacher Education course in Australia. Six teaching staff, all co-researchers for the study, contributed reflective data, and engaged in analysis and interpretation of the data via structured critical friendships. Insights related to four key themes were derived from the analysis: institutional and pedagogical factors; educator wellbeing, self-efficacy and professional identity; staffing support; and collegial professional learning. The implementation of BSL, while aligned with existing recommendations, produced significant challenges for educators in relation to institutional support and training, pedagogical practices, operation of BSL technologies, professional identity and self-efficacy. Cognitive overload was a prominent feature of the BSL teaching experience. On the whole, while drawing on existing skills and teaching experience, educators held significant concerns with the overall quality of student learning in BSL--especially for remote students. Training, practice, technical and co-teaching support, as well as collegial relationships, were important mediators of educator experience. The findings suggest that the implementation of BSL requires substantial investment in staffing, training, skill development, and opportunities for authentic, meaningful practice and prototyping. The findings also affirm the value of timely, organisationally supported and collaborative professional learning as part of BSL implementation.