Fox stations during the network's early years, channels 17 and 44 continued to program as de facto independent stations as the late-night talk show The Late Show Starring Joan Rivers was the network's only program initially; when Fox debuted its prime time schedule in April 1987, the network only carried evening programming on weekends, and would not carry seven nights a week of programming until June 1993. Until Fox began airing programming on a nightly basis, WDBB and WNAL aired movies (and later, syndicated programs) at 7:00 p.m. on nights when the network was not scheduled to air any programming. Despite covering roughly half of central Alabama over-the-air and the two stations maintaining a relatively strong program lineup, the signal of WDBB did not provide better than Grade B coverage (at best) within Birmingham proper. Due to the eastward location of its transmitter tower, WNAL's signal did not penetrate well into Birmingham either, only reaching as far west as extreme eastern Jefferson County. In addition, several major cable providers in the Birmingham market, including in Jefferson and Shelby counties, refused to carry the station for this reason. Ultimately, WDBB/WNAL was not profitable. After all efforts to increase the stations' cable coverage failed, Fox signed an agreement to make WTTO its new Birmingham affiliate and moved its programming to channel 21 in January 1991. Soon afterward, DuBose reached an agreement with Abry Communications in which WDBB and WNAL would convert into semi-satellites of WTTO and begin simulcasting its programming for the vast majority of their broadcast day, with separate syndicated programming airing during the three hours that the stations continued to program themselves. As part of the deal, WDBB/WNAL merged its stronger inventory of programming onto WTTO's schedule, with the local rights to some classic sitcoms on its schedule that it could not retain or move elsewhere on the schedule being sold to WABM (channel 68) in Birmingham, which converted into a general entertainment independent around the same time the WTTO/WDBB/WNAL simulcasting arrangement went into place. The station subsequently began identifying as "Fox 21", using the channel allocation of WTTO as a universal brand for it and its repeaters. The combination of WTTO, WDBB and WNAL provided a strong combined signal throughout the central third of Alabama that was comparable to those of ABC affiliate WBRC-TV (channel 6) and NBC affiliate WVTM-TV (channel 13). In 1993, Abry had purchased WDBB and