It happened about a week ago. I was on duty, sifting through a stack of screeners of second and third episodes of fall series, not feeling particularly eager to view any of them, and as my thoughts wandered I felt a pang of “Hey, wait a minute…” excitement.

The new season is underway, I thought, and that means fresh segs of “Lost” are coming soon…

For a split second, my mind raced, my heart soared and I lunged toward my computer to look up the premiere date. And then it hit me. Four. More. Months. Or at least three and a half. “Lost” won’t be back until early February. (I knew that already, of course, but after watching too many screeners in a row you often have to smack yourself upside the head to get the synapses firing properly again.)

It’s going to be worth the wait, no doubt. Our heroes — “Lost” exec producer/co-creator Damon Lindelof and exec producer Carlton Cuse — are using the time to painstakingly map out the flight plan for “Lost’s” remaining 48 episodes. “Lost’s” chief creative stewards and ABC announced an agreement back in May to bring the show to an end in 2010 end after three more seasons of 16 episodes apiece.

ABC’s decision to sked the show “24”-style without repeats over consecutive weeks makes perfect sense — ergo, the February preem date. It’s all very logical and forward-thinking, but when we were applauding these decisions a few months ago, I don’t think any of us rabid fans had a clue how tortuous it would be to have to wait so long. Drat and Deuteronomy!

But it’s just my luck that Lindelof and Cuse were cool and kind enough to respond to a pleading email from a jones-ing fan. The two got on the horn last week to discuss how their work process has changed in the new 48-episode world order.

“The biggest change is that it gives us the benefit of being able to plot and plan the remaining mythology of the show,” Cuse says.

Before there was a pre-determined end date, “it was always tricky for us to figure out how fast it could all unspool. This allows us to do a lot of macro-planning, and more opportunities to organize and strategize.”

At the end of last season, when the “Lost” scribes held their annual post-mortem before the summer hiatus, they began to think about how the long-term stories will unfold over 48 more hours. Each of the three remaining seasons has to have its own beginning, middle and end, natch, but now in the plotting of those 16-seg batches “we can draw back on a macro-level and begin to plant certain story ideas. We have a much better sense of how the ‘Lost’ mosaic will be filled in,” Cuse says.

The later on-air start means that the writers will be almost done with the scripts for all 16 episodes by the time series bows. Writers went back at it in mid-July; shooting began in August and they expect to be in production on segs 12 and 13 by the time the first one rolls in February. (Unless, of course, there’s a work stoppage among Hollywood scribes, which would be a horrorshow unto itself.)

And as such, “Lost’s” scribe tribe will have much less flexibility in the coming frame to “course-correct,” as Lindelof puts it. He and Cuse were quite candid and humble in acknowledging the complaints of fans about the tight focus of the storytelling in the first seven episodes of last season. (Not enough of the ensemble! the fans howled). And when they intro’d characters, Nikki and Paolo, who fell flat with the fan-o-sphere, the writers responded by promptly burying them alive. Primetime TV doesn’t get much more interactive than that.

In truth, Lindelof sez they’re not too worried about running afoul of fans, because the writers’ room collectively has a pretty good sense of when things are clicking — and when they’re not — at any given moment during production.

“We had the feeling with Nikki and Paolo that it wasn’t right about a month before the fans started reacting,” Lindelof says matter-of-factly. “We were already starting to think, ‘Maybe our instinct here has been wrong.'”

Lindelof notes that “Lost’s” storytelling quirks presents huge challenges, particularly at the start of each season. There’s no “Four months later” title slate that can set up a new frame of reference for characters or the plot. Even Fox’s “24” gets to hit the reset button at the start of each season. But on “Lost,” the season opener by necessity takes place moments after the credits rolled on the previous season’s finale.

“It can be hard to hit the ground running,” Lindelof admits. “It’s not like we can say ‘Well, it’s another year at Hogwarts,’ or we have the ability to scatter our characters around to new situations. If there’s a backlash (among fans) in our show it usually comes from how we start out.”

Now that the finish line is in sight, Lindelof and Cuse have a much better grip on the stories they need to tell and how the threads they’ve laid out so far need to weave together. It’s unlikely they would’ve attempted the flash-forward sequence featuring Jack and Kate in last season’s two-hour finale if they were still uncertain about their end-date, Lindelof says.

Telling stories in the past, the present and, starting with last season’s finale, the near future is also a high-wire act, Lindelof observes. It would’ve been reckless to present a vision of the future without having a firm grip on where their characters are heading.

“In most dramas the story takes you from point A to B to C. On our show you go from A to B, an then we go, ‘Here, look at V…and then let’s go back to C.’ You can’t just take those detours if you don’t have a good sense of where your big story beats are,” says Lindelof.

So did their grand plan for the characters change after they got the 48-and-out order from ABC in May? Or have they always had the broad strokes of the plot in mind, and now the focus is on story structures and pacing? These probing questions (which they’ve been asked a few thousand times before) were met with a pause, and then a Kerouac-ian response from Cuse.

“It’s like you’re taking a road trip from L.A. to New York,” Cuse says. “You know you’re going to end up in New York. But now you look at your itinerary and you know that you’re going to be in Cleveland on these three nights, and you’re going to be in Detroit on these two nights…”

Lindelof allowed that the show and its characters have taken on their own life at several points in the series’ run so far. He pointed to the additions of Elizabeth Mitchell as Juliet and Michael Emerson as Ben as situations where the actors were so good in the roles that the writers had little choice but to expand their storylines beyond their initial plans.

“Ben was supposed to be in three episodes of season two,” Lindelof says. “Now it’s impossible to (imagine) the show without him.”

Taking those kind of unexpected twists and turns is a big part of the creative turn-on of episodic television, Cuse says.

“A TV series is like an organic entity,” he says. “You have your plans, you steer it and tell it what to do, and sometimes it tells you what to do. Seeing those things (on screen) that you don’t expect — that’s the exciting part.”

With the lag time between production and premiere this season, the “Lost” writers must be working in bunker-like conditions in an effort to keep the plot leakage to a minimum, no?

Yes and no. Yes, they have clamped down “enormously” this year on the distribution of show materials outside of need-to-know circles, Cuse says. All of the casting info they circulate is based on extreme generalities, or in some cases, out and out deceptions.

“We always write fake sides for the stuff we send to talent agencies and (casting) breakdowns,” Cuse says. “We are casting characters under false pretenses…We come up with things that are analogous to the roles we really want.”

As for internal security concenrs, Lindelof and Cuse say they expect everyone on their core staff to act professionally and responsibly. Spoilers are going to happen — there’s no getting around that when people make a sport out of staking out the show’s production sites in Hawaii with telephoto lenses.

Lindelof and Cuse bank on the fact that “Lost’s” true-blue fans eschew the many spoiler-info sources out there in favor of enjoying the viewing experience to the hilt, and learning plot points the way nature intended them to be disseminated.

“You’re only going to see ‘The Sixth Sense’ for the first time once. There’s only going to be one time when you watch the movie and not know that Bruce Willis is really dead,” says Lindelof. “That’s what we pride ourselves on doing in our show, those kind of twists and turns that grab you. I think there’s a lot of responsibility to be taken on the part of the fans, and on the part of the press, to not destroy the viewing experience for people.”

At the same time, because of the fandemonium that the show inspires, it behooves them to sprinkle out a few tidbits during the off season, out of respect for the passion people have for the show and because complete radio silence only encourages the search for spoilers, Lindelof believes.

They to be savvy about managing the news they know won’t hold, such as actor Harold Perrineau’s return as a regular next season. Lindelof says they announced it at Comic-Con with much fanfare — and an appearance by Perrineau — because the July confab was the perfect setting to unleash such fan-pleasing news (though the official word got out a few days before after ABC boss Steve McPherson dropped a hint and then got into a tussle with reporters during the Television Critics Assn. press tour.)

At Comic-Con, “Lost’s” dynamic duo also preemed another tantalizing Dharma Initiative black-and-white training film with the haughty scientist who’s name is never the same.

Lindelof sez they’re also excited about an upcoming series of exclusive original “Lost” shorts coming to mobile platforms through ABC’s deal with Verizon (I’m guessing they’ll also wind up on ABC.com and/or iTunes at some point) and will be rolled out in a serialized fashion as part of the build up to the season four premiere. The shorts, featuring regular “Lost” players and produced under WGA, DGA and SAG auspices, will provide fans with a glimpse of “some really interesting ‘Lost’ puzzle pieces,” Lindelof promises.