PHILADELPHIA - Lawyers for the U.S. Postal Service were in court Thursday to defend accusations that service cuts are slowing down the mail and threatening the integrity of the presidential election.The latest hearing on the issue took place in federal court in Philadelphia, where the attorneys general from six states and the District of Columbia have sued.They argue that on-time delivery dropped sharply in July and has not fully rebounded as the nation battles a pandemic and prepares for an election that could hinge on mail-in ballots.MORE: 2020 ELECTION“There was a sharp dip in early July that hasn’t rebounded to where it was, even today,” Deputy Attorney General Aimee D.