No predictions loaded for 2031. This site serves NOAA predictions from its own store, and this period has not been fetched for Copper Harbor yet. Nothing is estimated or interpolated in its place. NOAA's own page for the station has the official table: tidesandcurrents.noaa.gov.
tidealmanac.site/us/ak/copper-harbor-9450369/2031
Copper Harbor, AK tide table 2031 (printable) · Tide Almanac