Patek Philippe CALIBRE CH 28-520 IRM QA 24H Mode D'emploi page 17

date correction
To set the date, actuate the correction push piece
between 9 and 10 o'clock as many times as needed
to display the current date.
If you wish to set the date to the 30th or the 31st,
proceed as follows:
1. Make sure neither the 30th nor the 31st is indi-
cated (if necessary, set the date to the first day
of the month).
2. First, correct the month with the push piece at
10 o'clock (see below).
3. Then correct the date to the 30th or the 31st.
The mechanism that advances the month display is
already active on the 30th and the 31st. If you do
not follow the described procedure, the calendar
might be desynchronized, but the integrity of the
mechanism would not be affected.
month correction
To correct the month, actuate the correction push
piece at 10 o'clock as many times as needed to
display the current month.
day of week correction
To correct the day of the week, actuate the push
piece at 9 o'clock as often as needed to display
the correct day.
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