iwc IW3794 Operating Instructions Manual page 29

the hands are turned back beyond midnight, but remains on the same day. If you
go past the end of the calendar's switching phase (i.e. beyond 2 a.m.) when turning
the hands back, you run the risk of the calendar advancing by one day for a second
time and thus indicating one day too many.
Setting when crossing the International Date Line:
– When crossing the International Date Line in a westerly direction (you enter the next
day, regardless of the time of day), simply turn the time forwards to the new local
time, and the date change will take place automatically.
– When crossing the International Date Line in an easterly direction (you enter the
previous day, regardless of the time of day), you must likewise set your watch for-
wards to the new local time. However, your watch will now indicate the wrong date
(one day too many). This incorrect date indication can be corrected by resetting the
hands twice, by 12 hours on each occasion:
– Setting the watch back by 12 hours during the afternoon between 2 p.m. and
8 p.m. will prevent the calendar from advancing at midnight.
– Setting the watch back by another 12 hours the following morning between
2 a.m. and 11 a.m. will synchronize the date display with the local date.
A Q U A T I M E R P E R P E T U A l C A l E n d A R d I g I T A l d A T E - M o n T h
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