JACKSONVILLE, Fla. — When the new Giants regime had no choice but to decline Daniel Jones’ fifth-year option, the franchise’s franchise quarterback succession plan following Eli Manning appeared all but over.

It’s not over.

There isn’t anyone at 1925 Giants Drive who isn’t rooting for this to work, even as general manager Joe Schoen and his minions fly around the country studying the bountiful 2023 Quarterback Class.

Jones will continue to state his case at TIAA Bank Field on Sunday against Trevor Lawrence and the Jaguars. There is a long way to go before anyone considers it a fait accompli, but:

—  Jones is, for the first time in his four-year career, showing that the Giants can win with him.

— He has been at his best when his best has been required in the fourth quarter.

— He has only Saquon Barkley behind him to frighten opposing defenses.

And though you don’t hear Giants fans hyperventilating over “Danny Dimes” all that much, Jones has performed effectively and efficiently enough for the powers that be to at least start asking themselves what he might look like with better weapons around him.

In the meantime:

— He has directed four game-winning drives.

— He has fixed his maddening ball security issues (two lost fumbles).

— He has honored the mantra of head coach Brian Daboll and Schoen: smart, tough and dependable.

— He has walked the treacherous tightrope between aggressive and reckless.

— He was Manningesque in being readily available for his team even as an ankle tried to betray him.

The more he wins, the lower the Giants will get to draft one of the prized quarterbacks. And the more he wins, the more of a moot point it might be.

John Mara was spot on when he told us in January: “We’ve done everything possible to screw this kid up since he’s been here.”

No one is screwing up Daniel Jones now (five touchdowns, two interceptions, 67.3 completion percentage, 41 rushes for 211 yards with two TDs), and no one is preventing him from attempting the start of his fourth-year leap … with his legs as a dangerous tool.

“I would say this building has always had belief in him,” Julian Love told The Post. “That has never changed, that has never waned ever in the past four years. Outside perception to the outside world is changing, is growing, he’s getting a lot more respect in the outside work, but that respect has never changed inside the building.”

Love is reminded that the people on the second floor of the building declined Jones’ fifth-year option.

“From a front-office perspective, I can’t speak on that, but I know players-wise, we’ve all really loved him and have appreciated him as a quarterback,” Love said, “and to see him succeed right now, I know everyone’s super proud and is thrilled for him.”

No one was under any illusions Daboll could mold Jones into Josh Allen. Only Josh Allen is Josh Allen. But Jones has clearly grown on Daboll. He is a more confident quarterback and is making better decisions under Daboll and offensive coordinator Mike Kafka than he ever had a chance to be and do under Joe Judge and OC Jason Garrett.

On a team that has grown to pride itself on its resilience, Jones is the personification of the word. He is the 60-minute quarterback. Never underestimate how critical it is for a quarterback in the New York market to refuse to flinch. Jones is the same guy every day. Still. The same as Eli used to be.

Manning had a better team around him and better offensive line in front of him when he won his first Super Bowl … in his fourth season. A tale of the tape after 43 NFL starts:

Manning: 22-21 record, 61 TDs, 49 INTs; 65-132-1 rushing, 23 fumbles, five lost.

Jones: 17-26 record, 50 TDs, 31 INTs; 219-1,236-7 rushing, 38 fumbles, 22 lost.

Jones needs more playmakers. In the meantime, if he keeps finding ways to win, he will have a fighting chance to play with them one day when Schoen finds them.