Delta Burke will get a chance to ride on Roseanne Arnold’s coattails starting April 6, as the sitcom “Delta” flies into the post-”Roseanne” slot replacing “The Jackie Thomas Show,” which will have completed its order for the season.ABC said no decision has been made regarding a return next season by “Jackie Thomas,” which is produced by Roseanne and Tom Arnold’s Wapello County Prods. in association with Lorimar. Insiders expect the show to be renewed, although the larger question is whether the sitcom can retain its current time slot. ABC also confirmed that another Universal TV sitcom, “Home Free,” will join the Wednesday lineup starting March 31 in place of “Doogie Howser, M.D.,” which will complete its run of original episodes the previous week. The “Delta” scheduling has been expected since the series lassoed a 20.5 rating, 33 share during a preview behind “Roseanne” in September. The show went on to struggle in its regular Thursday time period, averaging an 8.9/15 before being placed on hiatus. 11 originals ABC will return with 11 original episodes of “Delta,” meaning the show can run continuously through the May sweeps and that roughly a half-dozen installments will air before the web has to decide on renewing it for next fall. Exec producer Barry Kemp (“Coach”) recently resigned from “Delta,” citing “professional differences” with Burke (Daily Variety, Feb. 2). The sitcom is still produced by Kemp’s company, Bungalow 78 Prods., in association with Burke’s Perseverance Prods. and Universal. ‘Jackie’ tails off As for “Jackie,” the show has fallen precipitously off its lead-in of late, helping allow Tuesday to slip away from ABC into CBS’ win column. That gap also has been growing, with the show suffering a 36% drop from “Roseanne’s” rating and plunging 11 share points last week. The network has ordered a total of 18 episodes of “Jackie” and a dozen have aired. The headache for ABC remains the risk of antagonizing the star of TV’s top-rated sitcom by canceling the show or even denying it a post-”Roseanne” berth. Then again, observers point out that NBC contributed to its current troubles in much the same fashion, allowing hit series and stars to control coveted time periods with shows that lacked the appeal to stand alone once those anchor series were gone. “Home Free” stars Diana Canova and Matthew Perry as part of a three-generational family forced to live together, with Tim O’Donnell as exec producer. The show will air between “The Wonder Years” and “Home Improvement.” ABC has announced a number of other scheduling changes that will begin in early March.