iwc 5045, Operating Instructions Manual

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P O R T U G I E S E R P E R P E T U A L C A L E N DA R T O U R B I L L O N
– When crossing time zones in a west ­
erly direction, you can set the hands
of your watch back to the actual time
of day. When doing this, however,
you must not move back into the cal­
endar’s automatic switching phase,
i.e. beyond 2 a.m. If this situation
occurs when you are travelling west,
you should set the local time of your
destination before 10 p.m. You must
not turn the hands back between
10 p.m. and 2 a.m. This is because
the calendar does not move back­
wards by one day when 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 advan cing by