This is a longitudinal study that examines the systematic development of reflective teaching (RT) practices of the English Language Teaching (ELT) professionals of North Coastal districts of Andhra Pradesh namely Visakhapatnam, Vizianagaram and Srikakulam. The research tries to quantify reflectivity as it exists without any interventions, and evaluate what changes, if any, the year-long action research intervention produces. Based on the theories of John Dewey (1933) and Donald Schön (1983), the research examined how much baseline reflectivity exists and how much change the year-long action research intervention brings about. The study adopted the mixed method of quantitative and qualitative, and quantitative methods were used were the English Language Teaching Reflection Inventory (ELTRI), and qualitative method were teaching journals, video-recorded self-analysis and peerobservation reports. In total, 67 ELT practitioners from technical institutions and secondary schools were involved in the study. Quantitative results showed that the teaching experience was negatively correlated with reflectivity, with a clear “mid-career dip” for teachers with between 11 and 15 years of experience, and then a positive correlation for teachers with 16 or more years of experience. The qualitative longitudinal intervention, which employed the Reflective Teaching Model (RTM) and "Loop Input" enabled a gradual transition from the "technical rationality" towards "critical reflection" by making it possible for teachers to base their pedagogical actions on applied linguistics theory, instead of "common-sense" beliefs. Most barriers identified to sustained practice were systemic (82% time constraints, 65% lack of formal training). The study concludes that reflective practice and support by institutionalizing multilingual UDL (Universal Design for Learning) is necessary to improve the self-efficacy of teachers and learning outcomes of students in the region.