I always inferred he used 1917 because it includes the number 17 ... in other contexts he states 1918
L.A. County stay-at-home order likely to be extended through July to fight coronavirus
Los Angeles County’s stay-at-home orders will “with all certainty” be extended for the next three months, county Public Health Director Barbara Ferrer acknowledged during a Board of Supervisors meeting on Tuesday.
I’ve always thought that it was just a slip of the
tongue because of the movie “1917”.