Background In the early years of schooling, learning tends to resolve information gaps and decrease ambiguity, and within this structure, high performing students learn to thrive and maximise performance. This changes irrevocably in doctoral education. The prototypical doctoral student is striving to investigate a research gap for which there is currently no answer in the entire body of literature, requiring a leap into the unknown with no guarantee of understanding. Prior learning expertise cannot necessarily be trusted, and this vastly heightened uncertainty may impact students' interest in their studies, plans for a research-focused career, and doctoral completion intentions over time. To date, however, no prior study has investigated how perceptions of uncertainty in learning may longitudinally relate to these factors, nor how individual differences such as one's openness to experience might provide a buffer against any negative effects. Method This Stage 1 registered report presents plans for a 10-month longitudinal assessment of 400 doctoral students. At monthly intervals, students will report their instances of uncertainty in learning, completion intentions, outcome expectations, interest, productivity, and wellbeing. Results will be analysed with dynamic structural equation models, predicting key outcomes from perceptions of uncertainty in learning at the previous time point, with personality traits openness to experience and neuroticism as potential moderators. Results and discussion will be presented in the Stage 2 Registered Report.