Online learning has emerged as the "new norm" due to the COVID-19 crisis. Compared with institutions' and teachers' responses to online teaching, little is known about students' perceived influence of online assessment practices. The present study explored the perceived effects of learning-oriented online assessment on L2 students' feedback literacy and individual differences in feedback literacy development from an ecological perspective. We used multiple sources of data, including a survey on student feedback literacy, semi-structured interviews with two focal students, drafts produced by them and related teacher feedback, and supplementary data reflecting the online assessment practices in the course. Results demonstrated that the students held less favorable opinions of the online mode of learning in promoting feedback literacy. However, they perceived positively the development of feedback literacy in the aspects of appreciating feedback, developing judgements, and taking actions. Considerable variations were identified in the development of two focal students' feedback literacy, especially in the aspects of managing affects and taking actions. The findings revealed the negative influence of misalignment between micro- and macro- factors on student feedback literacy and how such a misalignment interacted with learner factors to influence individual students' feedback literacy when learning-oriented assessment (LOA) was implemented during COVID-19. The paper proposed a fine-grained model for developing student feedback literacy through learning-oriented online assessment. With a special focus on misalignment, the model provided insights into the interactional dynamics among learners, classroom, and larger contexts in using LOA to enhance student feedback literacy online. Relevant pedagogical implications for developing student feedback literacy within and beyond COVID-19 were discussed.