The Postal Service is preparing for a greatly increased number of gifts being mailed this holiday because of the pandemic. Sunday delivery will be expanded beginning Nov. 29 to high package volume locations. USPS already delivers packages on Sundays in most major cities. The mail season usually peaks two weeks before Christmas, as procrastinators complete their last-minute shopping. They’ve announced the shipping deadlines to get your presents to their destination in time for Christmas day. For most people sending retail packages by ground, Dec. 15th is the deadline. For priority shipping and first class mail it’s December 18th.