But after WAtoday reported on the case last year the Director of Public Prosecutions (DPP) appealed the sentence.

The appeal was allowed and on Monday the WA Court of Appeal resentenced Yamalulu to seven years and six months jail, more than double his original term.

In their decision published online on Monday, the Court of Appeal described Yamalulu's crime as a "frenzied, savage and relentless attack upon a vulnerable, unarmed and defenceless woman".

"We are satisfied, after considering all relevant facts and circumstances ... that the length of the sentence was unreasonable or plainly unjust," the Court of Appeal ruled.

"The sentence was not merely lenient or at the lower end of the available range. It was substantially less than the sentence that was open to her honour on a proper exercise of her discretion.

"In our opinion, the sentence of three years (and) eight months ... was not commensurate with the seriousness of the offence."

The Court of Appeal judgement noted Yamalulu's own legal team accepted the original sentence was inadequate and the offence was "at the upper end of seriousness".

Yamalulu's new seven year and six month term takes effect from February 2017.

He won't be eligible for parole until 2022.