The study aims to explore the trajectory of digital literacy development in Chinese EFL learners as facilitated by ChatGPT feedback in the context of L2 writing. In addition, the research seeks to identify factors that contribute to this developmental path, including learners' writing proficiency, teacher instruction, prior experiences with technology, adaptive expertise in using ChatGPT, and the complexity of assigned writing tasks. Employing a mixed-methods approach, data collection encompasses student surveys, reflective accounts of interactions with ChatGPT, writing drafts and revisions, as well as comprehensive in-depth interviews. The cohort comprises 34 undergraduate English majors from China. Spanning a total of 16 weeks, the research aims to produce a multi-layered understanding of the students' progression in digital literacy via data triangulation. The anticipated outcome is a detailed depiction of how Chinese EFL learners evolve in their digital literacy, particularly in utilizing ChatGPT for writing feedback.