get_period_and_ensure_valid_local_time

# File activesupport/lib/active_support/time_with_zone.rb, line 333
      def get_period_and_ensure_valid_local_time
        # we don't want a Time.local instance enforcing its own DST rules as well,
        # so transfer time values to a utc constructor if necessary
        @time = transfer_time_values_to_utc_constructor(@time) unless @time.utc?
        begin
          @time_zone.period_for_local(@time)
        rescue ::TZInfo::PeriodNotFound
          # time is in the "spring forward" hour gap, so we're moving the time forward one hour and trying again
          @time += 1.hour
          retry
        end
      end