Ballots, tax returns and other important mail may not get postmarked the day you turn it in, Postal Service warns

By Fredreka Schouten, CNN (CNN) — If you rely on postmarks when casting your ballot, filing your taxes or paying bills, a new US Postal Service rule makes it clear that you should plan ahead. Postmarks – which include a date stamp from the USPS – can offer proof that a piece of mail, such