This year the Beginning of Spring came before the Spring Festival, just as the line says: 'spring reaches the river before the old year is out'.
Tips
culture
The second line of the famous couplet in 王湾's 次北固山下: 海日生残夜,江春入旧年 'the sun rises from the sea while night still lingers, and spring reaches the river before the old year is out'. Moored on the Yangtze, the poet watches the new day and the new season arrive early, and the poem then turns to homesickness.
usage
旧年 here is the year that is ending, not 'last year'. When the solar term 立春, the Beginning of Spring, falls before the lunar New Year, spring has begun while the old year is still running, which is the moment the line catches.