NBC reportedly is mulling a wholesale schedule change that would involve shuffling shows on Monday, Wednesday and Thursday nights, in the process moving “Blossom” and “Seinfeld” to Thursday in an attempt to fortify the night’s fading comedy block.

Under the scenario floating around the network, NBC would move teen hit “Blossom” from Monday to 8 p.m. Thursday opposite “The Simpsons,” flop “Wings” into the 8:30 slot and set “Seinfeld” after “Cheers.” That shift seeks to establish the Castle Rock comedy as a possible replacement next season, since “Cheers” will close up the bar after this spring.

With “Seinfeld” leaving Wednesday to escape the power of ABC’s “Home Improvement,” NBC might try a drama in the 9 o’clock hour–possibly the new Barry Levinson-produced series “Homicide: Life on the Street,” which is scheduled to premiere after the Super Bowl on Jan. 31.

That preem date indicates that at least part of any potential shuffle wouldn’t take place until during the February sweeps, which begin in Nielsen on Feb. 4. ABC and CBS already have announced a number of lineup changes set to take effect in early January.

NBC wouldn’t confirm any moves at this time, and sources note that the discussed shifts haven’t been etched in stone.

Boost for ‘Seinfeld’

Still, it’s been speculated since shortly after the “Cheers” announcement that “Wings”–previously locked into its time period because both shows are produced by Paramount–would relocate so NBC could use the remaining “Cheers” run as a platform to boost “Seinfeld” (Daily Variety, Dec. 11).

Such a series of changes would leave two prominent series without a home: “A Different World,” the veteran Thursday comedy that got hammered by “The Simpsons” and ultimately moved back into its traditional 8:30 time period; and “Mad About You,” the TriStar TV Paul Reiser sitcom, which has struggled coming out of “Seinfeld.”

Left ‘Out’?

It also would displace the new NBC Prods.-Patti LaBelle vehicle “Out All Night,” which like “Mad About You” already has been picked up for the full season. “Night” could end up in “Blossom’s” slot following “The Fresh Prince of Bel-Air,” unless NBC opts to use that space to launch a new half-hour.

“Different World” and “Mad About You” might then be candidates for the Saturday lineup, currently composed of “Here and Now” (starring Malcolm-Jamal Warner, another in-house show), Columbia’s Norman Lear comedy “The Powers That Be” and the successful 9 o’clock hour of “Empty Nest” and “Nurses.”

Blossom vs. Bart

“Blossom,” from Disney’s Touchstone TV, scores big, especially with teens, on Monday but will have its work cut out for it against “The Simpsons,” a powerhouse with teens as well as kids and young adults. Such a matchup would take on added significance since both shows are currently being sold into off-network syndication and vying for similar time periods.

A Wednesday “Homicide” slot might be a mixed blessing: The series would benefit from being sandwiched between “Unsolved Mysteries” and “Law & Order,” but would face solid competition from “Improvement”/”Coach” and “In the Heat of the Night.” Then again, the alternative would probably be a 10 p.m. Friday berth –a tough hour to launch new series–should NBC give up on “I’ll Fly Away.”

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