WNTR-AM (1050), a daytime-only station, has been assigned a 5:15 p.m. sign-off for January by the Federal Communications Commission. It has therefore juggled parts of its programming: "Crossfire," with Tom Braden and Pat Buchanan, will air from 3:30 to 4 p.m., and Dr. Gabe Mirkin from 4 to 5:15 p.m. Starting tomorrow, the news/talk station will feature a weekly "Best of Mirkin" wrap-up at 1 p.m. WNTR has also switched Susan Forward to 10 a.m. and Owen Spann to noon weekdays . . . WRQX-FM (107.3) has announced some adjustments in its lineup, effective Jan. 14: Jim Elliott and Scott Woodside will remain at 6 to 10 a.m.; Sandy Weaver switches from nights to 10 a.m. to 2 p.m.; Gary Murphy follows at 2 to 6 p.m; Shadow Smith from 6 to 10 p.m.; Vinny Brown from 10 p.m. to 2 a.m.; and overnight with J.T. Stevens . . . Bill Tanner, former program director and morning man at WASH-FM (97.1), has joined WEZI in Miami, an outlet of Fairfax-based EZ Communications. The company said his contract is "a multiyear arrangement that guarantees Tanner in excess of $1 million.