I think it's already been established that was not the case.
She rang her family - in Perth (about midnight Perth time) and I seem to recall from the interview with her mother that it was the mother who answered the phone. I assume that it was a fixed-line phone - not a cordless, as she said she didn't want to disturb the father, so she'd get her brother up and he then went downstairs - presumably to another fixed line phone - to call Jill back.
Jill's husband Tom - in the interview video above - says that he called her perhaps 100 times between 2am and 8am, and the phone rang out then went to voicemail. About 8am it started going straight to voicemail, so presuambly the battery ran out at around 8am, or the phone was turned off about then - either by Jill or by somebody else.
That's my take on the phone thing, anyway. And yes, I still find it odd that she'd phone home at 2am Melbourne time, midnight Perth time, just to talk about her father, who is home and recovering from a stroke he had TWO WEEKS ago. Not exactly an emergency reason for a phone call in the middle of the night. There's still, to me at least, something odd about the whole phone call situation.
Also, when Tom refers to her going out with just her phone and a credit card, I think he would take it for granted that they would be in her handbag. I doubt she had pockets! She left her purse (what the Americans would call a wallet) at home, and just took the bare essentials.
The apparent planting of the handbag has me intrigued. WHY would somebody do that? Especially leaving the ID in it in the form of her credit card?
There are a lot of unanswered questions, apart from the obvious ones like what happened to Jill and where is she?