Dynamic written corrective feedback (DWCF) is a pedagogical approach that offers meaningful, manageable, constant, and timely corrective feedback on student writing (Hartshorn et al., 2010). It emphasizes indirect and comprehensive written error correction on short, daily writing assignments. Numerous studies have demonstrated that its use can lead to fewer language errors among undergraduate and pre-matriculated college writers (see Kurzer, 2018). However, the benefits of DWCF among second language (L2) graduate writers and the role of feedback timing have not been well examined. We analyzed timed writing samples over a 12-week intervention from 22 L2 graduate students who either received feedback on their writing throughout a semester, or postponed feedback until the last two weeks of the semester. Writing was analyzed for grammatical errors, lexical and syntactic complexity, and fluency. Results showed that neither timely nor postponed feedback led to significant improvement in grammatical accuracy or lexical complexity, but timely feedback did result in more fluent and complex writing. These findings suggest that the timing of feedback may be trivial for accuracy development but is more important for complexity among graduate writers. Teachers, teacher trainers, and writing administrators may use these insights as they plan curricula and design grammar and writing interventions.