Finishing work, school, or an activity earlier than usual (e.g., leaving work early).
今日は会議が早く終わったから、早上がりで5時に帰った。
The meeting finished early today, so I left early and went home at 5.
夏は暑いから、職場で早上がりになることがある。
In summer it's hot, so sometimes the workplace allows early leave.
部活が中止になったので、生徒たちは早上がりした。
Club activities were canceled, so the students left early.
An obsolete/colloquial term meaning entering elementary school a year earlier than one's peers; rare in modern usage.
古い記録には『早上がりで入学した』とあり、年齢が一つ上だったとある。
Old records note someone 'entered via haya-agari', indicating they were a year older when entering.