Once a leap year in our office.Are once a year route inspections based on the calendar year or the Postal Service business year?
L...M....B...O???PO-603 doesn't designate a date range, only the frequency.
523 Frequency
Management schedules at least one annual inspection of rural routes.
NRLCA mail count guide is similar.
512 FREQUENCY
All routes must be inspected at least once each
calendar year. An inspection must be conducted
either during or immediately preceeding the annual
count of mail and all special counts of mail.
Additional inspections may be made at other times of
the year.