NEW YORK — Fox pitched its three-pronged yearlong schedule to advertisers Thursday, declaring an end to the fall season as we know it.

The net’s sked, designed to carry Fox from June through next May, consists of major program launches in June, November and January.

Announcing the shift in strategy during a presentation at New York’s City Center, entertainment prexy Gail Berman said the rollout was built around Fox’s two major tentpoles, the Major League Baseball playoffs/World Series and megahit “American Idol.”

“This is no longer an experiment,” she told reporters earlier in the day. “Fox is altering the way this industry does business.”

Indeed, while Fox announced by far the most aggressive change in strategy, several networks have waved the 52-week schedule flag this week, including NBC, ABC and the WB.

Berman said she was “flattered,” but that only Fox was extensively changing the way it did business. “We not only have 52 weeks on the air, but we’re in 52-week development. I do not believe that if you ask my colleagues whether they were in that game that they could answer that with a straight face.”

Fox presentation kicked off with a bicoastal performance featuring last year’s “American Idol” finalists, Clay Aiken and Ruben Studdard (onstage in New York) and this year’s top two, Fantasia Barrino and Diana DeGarmo (live from Los Angeles).

Berman then took the stage and managed to unveil three schedules in less time than several networks take to announce one.

As previously announced, new dramas “North Shore” and “The Jury,” laffers “Method & Red” and “Quintuplets” and reality entries “The Casino” and “The Simple Life 2: Road Trip” join the net next month.

Then as expected (Daily Variety, May 20), in November, drama “House” and reality shows “The Billionaire: Branson’s Quest for the Best,” “The Next Great Champ” and “The Partner” will bow.

The new round of skeins hitting Fox in January include dramas “Athens,” “The Inside” and “Jonny Zero” and half-hours “Related by Family,” “American Dad” and “Kelsey Grammer Presents: The Sketch Show.”

Then, in summer 2005, several of this upcoming summer’s successful series may return, along with additional episodes of shows that launched in January.

Net also said several more nonfiction programs will float in and out of the lineup, including “The Complex: Malibu,” which airs this August.

In scheduling all the way through next May, Berman admitted that the sked could change, depending on how the new shows perform.

“There is always flexibility in the schedule for a breakout hit or in anticipation for failure,” she said. “Both contingencies have been thought through.”

The exec said she also anticipated some confusion, among advertisers and viewers, as Fox alters the way it launches its programs. To help get the word out, the net is reallocating marketing dollars.

“This is going to take some time. This is not an overnight thing,” she said. “It’s going to require some patience on our front. … When we talk about a revolution, we’re talking about it in every sense of the word.”

Fox sales president Jon Nesvig said the net decided to announce all three schedules this week at the behest of advertisers, who wanted a better idea of what they were buying throughout the year.

“One of the things advertisers have been asking in upfront is more information on what’s going to be on air,” Nesvig said. “We expect this will be nothing but a help to the sales department.”

As for the rest of the net’s lineup, biggest moves include shifting hit drama “The OC” to Thursday — not a popular move with series producer Warner Bros. TV. But Berman believes there is an opening for the sudser on that night now that juggernaut “Friends” has departed.

“Last season, this is where the show was originally scheduled to air, but we didn’t think there was an opening at that time,” she said. “It’s the biggest show on TV with teens, and we now think there’s an opportunity. We would like to seize that and stake our claim there.”

Berman also said bringing back critically acclaimed but low-rated “Arrested Development” was a no-brainer.

“It’s beloved by everyone at the network, by Jon and his (sales) group,” she said. “When we got into the scheduling room, it was a foregone conclusion. We know it’s had a modest run so far in terms of audience appreciation, but we hope to see that build in the same vein of ‘Seinfeld’ and ‘Raymond.’ ”

Also an easy choice was signing up for new segs of “Family Guy” (Daily Variety, May 20), which 20th Century Fox TV put back into production earlier this year.

“I believe this show was way ahead of its time,” Berman said. “It’s now a huge DVD hit and has a ready-made fan base eager for its return.”

Gone from the schedule are “Boston Public,” “Cracking Up,” “Luis,” “A Minute With Stan Hooper,” “Skin,” “Wanda at Large” and “Wonderfalls.”

On the reality front, Berman said she didn’t anticipate bringing back “Forever Eden,” “Playing It Straight” or “My Big Fat Obnoxious Fiance.” She is a bit more open to the return of “The Littlest Groom.”

“Maybe we’ll do that one again; that was kind of fun,” she said.