Saturday classes (2 hrs, from Oct 31), homework due dates, mock exams, and the official USAAIO deadlines in one place.
Click any item for details. 上课、作业截止、模拟考试和官方重要日期，一目了然。点击条目查看详情。
—days until registration closes (Jan 31) 距报名截止
—days until Round 1 (Fri Feb 19) 距第一轮比赛
—next homework due 下次作业截止
Coming up · next 3 weeks 近期安排
Official 2027 USA-NA-AIO dates 官方重要日期
Date
Event
Details
All official times are U.S. Eastern Time
Round 1 = Friday Feb 19, 2027, 12:00–3:00 pm ET (= Sat Feb 20, 1:00–4:00 am in Taipei/Beijing).
Always re-check usaaio.org before the big days.
官方时间均为美国东部时间，请以官网为准。
Class and homework dates come from the Class Schedule; homework is due at the start of the next class.
Official dates from usaaio.org (checked Sep 29, 2026). Rebuild with python3 99_admin/build-calendar.py.