Abstract
<jats:title>Abstract</jats:title> <jats:p>As HyFlex instruction has gained popularity in higher education, instructors face new demands when developing skills tailored to dual-modality teaching. While prior studies have examined instructors’ experiences with HyFlex through single-point surveys or interviews, researchers have yet to explore new instructors’ adaptation to HyFlex teaching over time. This qualitative study with sequential qualitative-quantitative mixed data analysis investigates the longitudinal HyFlex teaching experiences of two new instructors to understand how their perceptions, challenges, and instructional practices evolved throughout a semester in undergraduate, project-based design thinking course. Data were collected through weekly reflections and interviews over ten weeks across semester. We employed sequential qualitative-quantitative mixed analysis, combining inductive thematic analysis, qualitative time series analysis, and frequency analysis using text mining. Results revealed that new instructors primarily focused on technology integration, class preparation, engaging both remote and in-person students, setting expectations, and defining HyFlex instruction. Frequency analysis showed that technology integration was the most discussed theme, while defining HyFlex was the least. The findings were interpreted through the lens of the Technological, Pedagogical, and Content Knowledge (TPACK) framework. Instructors perceived Technological and Pedagogical Knowledge as the most needed TPACK domain for improving teaching in HyFlex as the most needed for improving instruction in HyFlex teaching. Practical implications for teacher development and institutional support are discussed, along with recommendations for future research.</jats:p>