The aim of this study is to investigate the wide array of school principals’ motivational factors and increasing and decreasing impact of the Covid-19 pandemic over these. By utilising the job demands-resources (JD-R) model as a theoretical framework, this detailed longitudinal mixed methods study investigates the experiences of 104 public school principals from six groups in the context of differences between pre-, during- and post-pandemic and highlights the job demands and resources that hinder or enable their motivational impetus. Findings were that pandemic and post-pandemic periods show an increasingly higher level of work overload and job demands. Pandemic results showed increased job resources in the form of support and recovery, but these declined post-pandemic. The strongest factors though were the decline in motivation and enjoyment of work post-pandemic, with reduced optimism and higher risk of turnover, resulting in a lower sense of wellbeing. The study is the first longitudinal mixed methods study of school principal motivation and contributes to the literature on the inter-relationships of motivation on the JD-R model and change in relation to the Covid-19 pandemic impact.