John Leathem, 32, stabbed the defenceless teenager 61 times and inflicted a total of more than 140 injuries when she stopped for a breakfast roll at his Delicious Deli in Clydebank, West Dunbartonshire, on March 19.
Despite claims he was in “a panic”, he cleaned up his crime and dumped the 15-year-old’s body in bushes near Great Western Road two days later.
The businessman, who admitted Paige’s murder, was given a mandatory life sentence at the High Court in Glasgow in October and ordered to spend at least 27 years behind bars.
He began his bid to appeal against the minimum jail term later that month and will have his case heard by senior judges at the Appeal Court in Edinburgh on Friday.
Paige’s mother Pamela Munro - who has said there is “no sentence high enough” for the child killer - has branded Leathem’s court move “cruel” as she prepares to spend her first Christmas without her daughter.
Ms Munro and the family have been campaigning against any reduction in Leathem’s sentence since they became aware of his appeal plans.
A petition opposing any reduction in his jail term has been signed by around 11,000 people.
Ms Munro, who has three other children, recently told the Sunday Mail: “Even if he got out at 59, he’d still have a life, so 27 years isn’t long enough. He’s totally deluded. This appeal is cruel.
“With the appeal being on December 23, there is no way that our first Christmas without Paige can be a normal one - as much as we might try to make it that way for the kids.”
Ms Munro also described how first offender Leathem appeared emotionless when she went to his shop while her daughter was missing nine months ago to talk to him about putting up posters to help to find Paige.
“Looking back, he was so cold,” she said.
Sentencing judge Lady Rae described the killing as “truly reprehensible” and “impossible to comprehend”.
She added: “The circumstances of the crime... disclose that this was a savage and frenzied attack.”