Heckingbottom, 41, was relieved of his duties by the Leeds United board back in June.
After replacing Thomas Christiansen in February, his side won just four games from 16 to finish 13th in the Championship.
Heckingbottom was replaced by Marcelo Bielsa who has made an impressive impact at Elland Road with Leeds currently sitting second in the table.
But with the competitive nature of the division, the former boss insists it’s no guarantee that the West Yorkshire giants will seal their return to the Premier League.
“They have all their eggs in one basket now in terms of this season or next [promotion],” Heckingbottom exclusively told Express Sport.
“For this sort of hierarchy, they’ve got to do it, they’ve committed to it and are going to give it a good go in terms of finance and throwing everything they can at it.
“Certainly this year or next without a doubt [they will be looking to go up].
“The league is so competitive and challenging that whilst people have ambitions to go up, there is no guarantee.
“Without a doubt it’s going to be tough, and whoever does it will deserve it because it’s a big grind, 46 games.”
Heckingbottom, who left Barnsley for Leeds less than a year ago, is now raring to go and keen to get back into management but is waiting patiently for the right club to come calling.
“There was a list of things I wanted to do to be in a better place for when I go back in,” he said.
“That was great, whilst at the time I could have never seen a benefit in it [being out of work].
“I addressed a lot of things but now I’m chomping at the bit and ready to go, one thing I am missing is that craziness and the job and the games, I’m missing it all.
“I’m now looking to get back in at the next opportunity. I’ve had quite a few [offers] but they just weren’t right at the time.
“I want to be successful, I’ve learned a lot under three different ownerships, three different experiences in different roles, nothing is ever going to be perfect.
“If any manager or coach is sitting about waiting for a perfect job then they may as well retire.
“As long as you know the restrictions of what you’re working, there’s an honesty there.
“You’re working together, it’s got to be a ‘we’ thing, that you’re part of the key decision makers at the club. If you’re working together then that’s all you can ask for.”