It is vital that in-service teachers transcend their professional knowledge, towards a recurrently developing research base about transformative social justice issues. This paper provides a theoretical lens from a South African education policy perspective on how in-service teachers could develop professional knowledge about transformative social justice teaching in public schools. Scholars argue that when in-service teachers surpass their professional knowledge base, it empowers them to transform learning spaces. Discourse analysis was applied to the "Continuous Professional Teacher Development" (CPTD) policy to understand professional knowledge and to identify transformative signposts for social justice teaching emerging from the policy. The findings show that the main barrier to professional development is a perceived lack of attention to the value and applicability of transformative social justice teaching practices for in-service teachers, while teaching and engaging in CPTD activities. Conclusions and recommendations were drawn based on the analysed data. The study recommends that for in-service teachers to perform more competently in their learning spaces, while maintaining the reputation of both their designation and the profession, they must engage in a continuous process of professional development.