Heke was assessed as above average or high risk of further sexual offending and a high risk of violent crimes.
In February 2017, the man approached a woman in central Dunedin and propositioned her.
She rebuffed his advances but Heke was undeterred.
He followed her up High St and despite her continued protestations, ushered her into a secluded walkway where the violations took place.
After being given Heke's name by friends, the woman found him on social media site Facebook and told him she would not go to police but wanted an apology and an assurance he would not attack anyone else.
"I'm really sorry. I won't ever do that again. You have my word ... u r [sic] safe," he responded.
That acknowledgement became crucial evidence for the jury at trial and he was found guilty of the sexual attack.
Heke had convictions for indecent assaults in 2005 and 2006 and was on parole after serving time for serious violence when the rape took place.
In October 2018, he had 15 months added to his sentence after he punched a man in prison and left him with brain damage.
The Parole Board said some planning had to be put into Heke's case which could mean a transfer to another jail.
"Location may be instrumental in the formulation of an appropriate release plan and obtaining community support," Judge Crosbie said.
"Mr Heke understands that he has some work to do."
He will next see the board in May next year.
Sexual harm - Where to get help
If it's an emergency and you feel that you or someone else is at risk, call 111.
If you've ever experienced sexual assault or abuse and need to talk to someone, contact Safe to Talk confidentially, any time 24/7:
• Call 0800 044 334
• Text 4334
• Email support@safetotalk.nz
• For more info or to web chat visit safetotalk.nz
Alternatively contact your local police station - click here for a list.
If you have been sexually assaulted, remember it's not your fault.