A former air force serviceman who almost killed a fellow veteran in a violent Anzac Day attack could apply to be released from prison in days — despite only being sentenced on Monday.

Kymbol Sheldon, 57, told the navy veteran he was going to kill him before assaulting the man in an unprovoked attack at an Adelaide pub in 2022.

WATCH ABOVE: Backdated parole could see man who almost killed a veteran apply for release in days

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The Supreme Court heard the pair met for the first time at the Elizabeth RSL on April 25, 2022, before travelling to another venue and later sharing a taxi to the Smithfield Hotel.

Inside the hotel, Sheldon glassed the decorated veteran several times, causing catastrophic facial injuries.

Kymbol Sheldon, 57 glassed another veteran on Anzac day 2022. Credit: 7NEWS/Facebook

CCTV played in court showed Sheldon swinging a beer bottle at the victim’s face repeatedly, then chasing him as he tried to escape.

The victim lost about 1.5L of blood, lost his pulse and was revived twice by paramedics.

Sheldon was jailed for seven years on Monday.

But his four‑year non‑parole period was backdated to April 2022 — meaning he can apply for release within days.

The victim’s sister Melanie said the decision “hurts” her family.

“My brother will be quite shocked in relation to this,” she told 7NEWS outside of court on Monday.

“We expected an offender with an antecedent history of severe violent offence in the community would have, it would have been a higher sentence imposed.”

Melanie said the family only learned the full extent of the violence during the court process.

“I had no idea at the level of detail and vulnerability that my brother had at the hands of this person and that the words that they said before the attack was that they would kill him,” she said.

The family is now pushing for stronger legal protections for veterans, similar to those already applied to police and paramedics.

“We would like to see an expansion of the current legislation which protects emergency services and the definition of that expanded to current or former personnel at commemorative occasions,” Melanie said.