The 2016 New Orleans Jazz Fest schedule won’t be revealed until January. But it’s not too soon to speculate about who will, or won’t, be on the roster. Instead of fantasy football, call it “fantasy festival.”

Though indigenous Louisiana artists fill the majority of the 500-plus performance slots on the festival’s 10 stages, the main Acura, Congo Square and Gentilly stage headliners inevitably generate the most excitement and debate. In recent years, Jazz Fest producer/director Quint Davis, his team at Festival Productions Inc.-New Orleans and their partners at AEG Live have grown more adventurous. Each lineup includes at least a few surprises, i.e. Pitbull and No Doubt in 2015.

As the music industry basically shuts down for the holidays, whatever bookings weren’t confirmed this past week likely won’t be nailed down until early January. Thus, the schedule of what is officially the 2016 New Orleans Jazz & Heritage Festival presented by Shell is still in flux. And nothing is official until the festival says it is.

However, the “nopes” and the “maybes” are starting to come into focus.

To qualify as “maybe” for Jazz Fest, an act must satisfy the three A’s: Availability, affordability and appropriateness. At the very least, he, she or they must be on the road this spring and have open dates that coincide with Jazz Fest, which runs April 22 to May 1.

And they can’t already be booked for their own, stand-alone concert in New Orleans. So scratch Duran Duran, the Cure, Rihanna, Maroon 5, Mumford & Sons, 311, Fall Out Boy, Selena Gomez and Josh Groban from the list of potential Jazz Fest acts. Duran Duran headlines the Smoothie King Center on the festival’s first Sunday, so Simon LeBon and company could conceivably pay a visit to the Fair Grounds and grab some Crawfish Monica. But chances are you won’t see them jamming at the Jazz Tent.

Major festivals generally prohibit headliners from performing at other festivals within a certain number of miles and days. The Hangout Festival in Gulf Shores, Alabama, is May 20-22, barely three weeks after Jazz Fest, and only a three-hour drive from New Orleans. Hangout’s headliners include The Weeknd, the breakout R&B star of 2015, as well as Alabama Shakes and Florence + the Machine. Therefore, all three are likely ineligible for Jazz Fest. Additionally, Florence + the Machine closed the opening night of the 2015 Voodoo Experience in City Park, which was probably reason enough for Jazz Fest to pass on them this year.

Adele, whose multi-million-selling “25” is a global phenomenon, is touring Europe this spring; her American tour doesn’t launch until July. And on both continents, she’s only playing indoor arenas. So you won’t hear “Hello” at the Fair Grounds, unless somebody else covers it.

Neither will you see country leading men Luke Bryan, Jason Aldean or Eric Church. They’re already booked for the 2016 Bayou Country Superfest in Baton Rouge, which is also produced by Festival Productions and AEG.

The Dixie Chicks are launching their first tour in 10 years on June 1. They’d be great at the Fair Grounds, but it’s highly unlikely they’d be ready to play the festival a month before the official start of their tour.

Country singer Carrie Underwood is in Louisiana the first weekend of Jazz Fest for gigs in Bossier City on Friday, April 22, and Lafayette on Sunday, April 24. Given those competing concerts in such close proximity, she is unlikely to end up in New Orleans on April 23.

The Doobie Brothers and Journey are out. Their joint tour, produced by AEG rival Live Nation, launches May 12 in California.

And I hate to disappoint the headbangers, but even though AC/DC is on the road in North America this spring, they’re too heavy for the festival. To date, past appearances by Foo Fighters and the Black Keys have pretty much defined the outer limits of Jazz Fest’s tolerance for amplified guitars.

Now for the fun part: Acts that are at least theoretically possible — and in some cases, probable — for the 2016 Jazz Fest.

During the Allen Toussaint tribute concert at Le Petit Theatre du Vieux Carre on Dec. 8, Paul Simon let slip that he’d be back for the festival. Which certainly makes sense. He’s been there before, with his own band in 2006 and as half of Simon & Garfunkel in 2010. Plus, he and Davis are buddies.

Bob Seger recently confided to Billboard magazine that he plans to check several experiences off his bucket list in 2016, including a Jazz Fest gig. If that pans out, Seger would likely close the Acura Stage on a Saturday. He appeals to the same broad, Baby Boomer audience as such previous Jazz Fest headliners as Elton John, Billy Joel, Eric Clapton, Tom Petty, Bruce Springsteen, Rod Stewart, Fleetwood Mac and Bon Jovi. Seger tops the increasingly short list of such artists who are still vital artistically and viable commercially, but have yet to plug in at the Fair Grounds.

Also, Michael McDonald, the oft-parodied former voice of the Doobie Brothers, told the Omaha World-Herald that his first show of 2016 will be at Jazz Fest.

And according to a tour schedule on the ECM Records web site, acclaimed modern jazz drummer Jack DeJohnette, saxophonist Ravi Coltrane and bassist Matt Garrison are bringing their trio to Jazz Fest on April 23. That’s an early rebuttal to the annual “there’s no jazz at Jazz Fest” argument.

After scouting the touring landscape for early 2016, several other possibilities, however remote, emerge.

The Avett Brothers are available on both Sundays of the fest, as well as Thursday, April 28. But making any of those dates would require flights either from or to gigs in Chicago and California.

Bonnie Raitt’s tour schedule would accommodate a Jazz Fest stop. She’s in Houston on April 29, then has no other announced gigs until Nashville on May 3. Van Morrison is in Atlanta on April 24. Both are Jazz Fest vets, and both are due for a return visit.

Andrew Bird plays April 22 in St. Louis, before traveling overseas for an April 30 date in Dublin. Maybe he’ll find his way down the Mississippi River to New Orleans first.

Ben Harper & the Innocent Criminals, an act that dovetails nicely with Jazz Fest’s recent aesthetic, concludes a spring run in Asheville, North Carolina, on April 23. Or do they?

Several other marquee “possibles” are long shots at best.

Will Smith plans to take a break from acting to tour with his old partner DJ Jazzy Jeff. They’d be fun to see at the Congo Square Stage, but it’s still not clear the tour is happening.

Bruce Springsteen & the E Street Band hit the road in early 2016 in support of the deluxe reissue of “The River.” The run concludes in Los Angeles in March. Springsteen has presided over three tremendous sets at Jazz Fest, in 2006, 2012 and 2014. But it’s probably a little too soon for a return visit.

The Red Hot Chili Peppers are slated to release a new album in 2016. They’ve already announced an appearance at Ohio’s Rock on the Range festival, which runs from May 20-22. And they are big fans of the Meters in particular and New Orleans in general.

Technically, Coldplay could make it to Jazz Fest. After a stop at the Super Bowl halftime show, they’re touring stadiums in South and Central America this spring. Following an April 16 date in Mexico City, their next announced show isn’t until May 24 in France. But bringing them to North America for only one show might be prohibitively expensive.

We’ll find out in January.

Follow Keith Spera on Twitter, @KeithSpera.