Watchtower can not get rid of 1914. Too much of their unique extra-biblical theology is built on this date.
Jesus was enthroned in 1914, Christendom was rejected in 1918, the apostles were raised to heavenly life in 1918 and the Faithful Slave (Watchtower directors) was appointed at Brooklyn headquarters in 1919.
If 1914 goes, so does GB authority.