NBC has yanked the freshman sitcoms “Out All Night” and “Rhythm and Blues,” after their disastrous return to its schedule last Friday, and replaces the two starting this week with the in-house hour “Secret Service.”NBC, in confirming the scheduling shift, wouldn’t say when the shows would return. The network has six episodes remaining of “Out All Night,” an NBC Prods. series starring Patti LaBelle that received a full-season pick-up, and seven left of “Blues,” an ensemble comedy from Twentieth TV. “Secret Service,” which normally airs Sundays at 7 p.m., will air tomorrow and March 5 in the 8 o’clock hour occupied by the two comedies. NBC had previously scheduled a special “Days of Our Lives” and the “Soap Opera Digest Awards” for prime time Feb. 26 (the final Friday of the current ratings sweeps) and an ice skating spec March 12, with no additional Friday scheduling set beyond that date. “Out All Night” pulled in a 5.0 rating, 9 share in Nielsen last week and “Blues” tapped out a 4.4/8, with each program pulling a 7 share among adults 18- 49 and running a distant fourth in its time period, unable to make any headway against established ABC and CBS comedies. By going to “Secret Service,” a dramatic reality program, NBC returns to its strategy from last fall, when it programmed half-hour reality shows “Final Appeal” and “What Happened?” in that hour. “Rhythm and Blues” and “Out All Night” originally aired on Thursday and Saturday, respectively, at 8:30 p.m.