Teacher Recommendation Deadlines

<p>I planned to mail my teacher recommendations tomorrow, but I just realized that New Year's Day is regarded as a federal holiday, and that the Post Office may be closed January 2nd due to the observation of former President Gerald Ford's death.</p>

<p>My question is, do these recommendation letters need to be postmarked by January 1st? I cannot get it sent tomorrow, and the earliest time I could send it is Friday (if the Post Office is open) with the latest time being Saturday. If these documents are not postmarked by this date, will my application be thrown out?</p>

<p>I've been told there is some leeway when it comes to recommendations -- but the letters do have dates on them as to when they were written. Can anyone shed some knowledge on this topic?</p>