Start applying between September and November, before your February graduation. Visas take 1–2 months to process, so secure a job offer at least 2–3 months before graduating. If the post does not clearly state that “only Korean citizens are eligible to apply,” I strongly recommend calling or emailing the HR team directly. When making an inquiry, communicate your questions with a professional attitude. You must clearly state that you are planning to obtain a doctoral degree in your field of expertise and that you are able to meet the valid qualifications for a professional visa (F-2-7S).