Have your mail forwarded to a friend or relative. At whatever interval you agree upon, call that person, go through it to eliminate the junk and have them forward the remainder to wherever you wish via priority mail (USPS can provide you with prepaid priority envelopes which make this more convenient for your sender). If you don't know a specific address where you will be have them send it you via General Delivery to a post office in the town you will be near a week from then. Although 98% of P.O. will accept general delivery mail, a few do not. Best to call ahead to make sure. You will need ID when you pick up your mail. I suggested giving your sender 1 week notice, but in over 13 year of doing this fulltime we've only had priority mail take more than 3 days once and that was 5.