Ran across this info on Military.com

Military Report - Deadlines For Holiday Military Mail: "Deadlines For Holiday Military Mail Week of October 22, 2007 Stars and Stripes reports that the deadlines for military postal mail reaching all destinations by Christmas are: 1) Nov. 13 for surface mail (mail going by truck or ship), 2) Nov. 27 for space-available mail, 3) Dec. 4 for parcel airlift mail, 4) Dec. 11 for priority mail and first-class letter and cards, and 5) Dec. 18 for express mail. 'These deadlines apply to everyone,' said Yvonne Radloff, command postal training manager for the 2nd Air Postal Squadron at Ramstein Air Base, Germany. No matter where mail is sent, either to the United States or downrange, Radloff said that it will usually get to its destination within 10 days. To find more deployment news and resources, visit http://www.military.com/deployment."