What is Early ?
Early is (adv) 1. before the usual time The plane arrived five minutes early. We must get up early tomorrow morning if we want to catch the first boat to France. 2. at the beginning of a period of time We went out early in the evening. The snow came early in the year. (adj) which happens at the beginning of a period of time, or which happens before the proper time We picked some early vegetables. I caught an early flight to Paris. These flowers open in early summer. at an early date soon The meeting must be held at the earliest date possible. to take early retirement to leave a job with a pension before the usual age for retirement (NOTE: earlier earliest)
source: Easier English, Student Dictionary Upper Intermediate Level