With increasing integration of AI into L2 writing instruction, there is a growing need to examine how L2 writers interact with AI tools and how the nature of this interaction develops over time. This study examined students’ self-directed interactions with ChatGPT during take-home writing tasks and explored changes in their perceived benefits over ten weeks of use. Data were collected from university students enrolled in beginner-level EFL writing courses who completed ten weeks of writing tasks. Students’ weekly reflection notes on ChatGPT interaction for feedback were analyzed through inductive coding, and temporal changes were examined using repeated-measure ANOVA with post hoc tests. Additional data included ChatGPT chat histories, pre-/post-writing tests, and an end-of-semester survey. The analysis of student reflections identified six major areas of perceived benefit from ChatGPT feedback: vocabulary, grammar, mechanics, content, organization, and metacognitive awareness. Over time, reflections related to grammar and mechanics decreased significantly, whereas content-related reflections increased steadily. Taken together, the findings of this study indicate that sustained interaction with ChatGPT may foster developmental changes in how students use the tool, shifting from form-focused error correction to more meaning-oriented refinement.

I. Introduction
II. Review of Literature
III. Research Method
    1. Participants
    2. Data Collection
    3. Data Analysis
IV. Results and Discussion
    1. Key Areas of Perceived Benefits of ChatGPT Interaction
    2. Temporal Changes of Students’ Weekly Reflection on ChatGPTFeedback
    3. Changes in Students’ Writing Proficiency Over Time
V. Conclusion
    1. Summary of Findings
    2. Pedagogical Implications
    3. Limitations
References
APPENDICES
    Weekly Writing Example – First Draft (Student A)
    Weekly Writing Example – Revised Draft (Student A)
    Reflection Note Example (Student A)
    Pre-assessment Writing Example (Student A)
    Post-assessment Writing Example (Student A)
    Survey Questions Sample

• Hyeyoung Cho(Hankuk University of Foreign Studies)