The zone's own offset at a UTC instant, minutes east: before 1970 the shipped history, which prepareLocalTime must have loaded, as for resolveLocalToUtc (an instant before 1970 throws until it has); from 1970, and in the fixed zones, Intl.
prepareLocalTime
resolveLocalToUtc
The zone's own offset at a UTC instant, minutes east: before 1970 the shipped history, which
prepareLocalTimemust have loaded, as forresolveLocalToUtc(an instant before 1970 throws until it has); from 1970, and in the fixed zones, Intl.