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My interview is scheduled at 12:00. In my interview invitation the interviewer asks me to call him when I arrive, so he can pick me up at the reception. This is a rather big company where he might have to walk 5-10 minutes to get me. Due to the train connection I will be there about 45 minutes early.
Should I call him at 12:00 sharp or ~10 min earlier so he can pick me up at 12:00?