‘‘The Beatles will never get back together, and David Lee Roth will never again sing with Van Halen.’’

Or so said Alex Van Halen once upon a time (actually, just three years ago.)

Well, the drummer was half right. The Beatles, we’re quite certain, have scrapped any plans for a reunion. But Diamond Dave is back in the Van Halen fold for the first time in 24 years. OK, so Michael Anthony has been kicked to the curb, preventing nitpickers from calling this a complete ‘‘reunion.’’ A look at the band then and now shows that a few things have changed over the years.

1984

Michael Anthony

Life for Michael Anthony circa 1984: Chug some Jack Daniel’s, add falsetto backing vocals to Panama and Running With the Devil, act as a firewall between the Van Halen brothers and the band’s singer and cash monthly royalty checks. Perhaps the smartest man in the band, he stuck with that winning formula for the next 20 years.

David Lee Roth

With a head of hair Phyllis Diller would be proud of, a closet packed with spandex and the ability to run his mouth longer than a drum solo, Diamond Dave was leg-kicking at warp speed toward his career zenith. All he needed was proof he didn’t need the rest of Van Halen around to slow his multimedia rocket ride, and that came a year later in the form of a four-song EP. MTV ate up his leering lounge-singer persona with a spoon, and old fans burned by Van Hagar’s synth sound had a reason to flash devil horns again after Roth assembled a crack band to ape his old one for his first full album, Eat ’em and Smile.

Alex Van Halen

In 1984, Alex Van Halen’s job description was simple: Keep time, have his brother’s back, collect 25 percent of the revenues and give the band a 10-minute Jack Daniel’s break while he indulged his inner Neil Peart with a drum solo.

Eddie Van Halen

Life was one long after-party for the guitar god in the mid- ’80s: His band had crossed into Casey Kasem territory with 1984, he had the signature solo on Michael Jackson’s Beat It and despite his despised dabbling in synths, Eddie still reigned supreme with the guitar mags that crowned the kings of fret board pyrotechnics. On the home front, celeb writers cooed about his 4-year-old marriage to Valerie Bertinelli. And — looking ahead — he was about to prove Van Halen could sell tens of millions of albums without Roth.

2008

David Lee Roth

The spandex and hair are history, and his leg kicks are about waist-high these days, but Roth’s Cheshire grin is still plastered to his face. And why not? The reunion gig he’s been pining for has saved Diamond Dave, 53, from the odd jobs he filled his days and nights with for the last 20 years: riding shotgun in a New York City ambulance, sharing the stage with archnemesis Sammy Hagar, crash-landing spectacularly as the heir to Howard Stern’s radio show and playing embarrassing bluegrass covers of his old music.

Alex Van Halen

At 54, Alex Van Halen’s job description is simple: Keep time, have his brother’s back, collect 25 percent of the revenues and give the band a 10-minute ginseng-tea break while he indulges his inner Neil Peart with a drum solo.

Wolfgang Van Halen

Where do you go to replace a stocky bass player? Eddie found one in his house when he tapped his 16-year-old son, Wolfgang, to take over for Michael Anthony. The original bassist’s sin that kept him off this tour: When Van Halen was on blocks, he toured with singer non grata Sammy Hagar. Anthony (who was a contract player on the 2004 reunion) learned he wouldn’t be touring with his old mates via the Internet. He says his loyalists — if they, indeed, exist — should relax, blogging, ‘‘Don’t judge his son, Wolfgang, too hard, because he’s the innocent guy in this whole thing.’’

Eddie Van Halen

He still looks ripped without the shirts he refuses to wear, but don’t be fooled: The bill came due with interest for the success and excess of the ’70s and ’80s. Eddie, 53, needed a hip replacement in 1999, a cancerous tumor removed from his tongue in 2000 and a stint in rehab in 2007. His marriage to Bertinelli crumbled, and Warner Bros. decided they’d heard enough of Eddie and his band after the Gary Cherone Experiment sparked a dry spell that rages on 10 years later. Eddie didn’t even make his band’s induction into the Rock and Roll Hall of Fame last year.

Ain’t talkin’ ’bout love

How hard can it be? One guy sings, the other plays guitar and together they print money. Well, as a guy with big hair once sang, ‘‘I found the simple life ain’t so simple.’’