Mr Lehrmann's defamation cases against two media outlets and a pair of high-profile journalists returned on Thursday to the Federal Court, where he gave evidence last week.

He claims Network Ten and presenter Lisa Wilkinson defamed him in February 2021, when The Project aired an interview in which Ms Higgins alleged an unnamed colleague raped her at Parliament House.

Mr Lehrmann also alleges news.com.au political editor Samantha Maiden and the website's publisher, News Life Media, defamed him on the same day in an online article about the allegations.

The 27-year-old, who denies any form of sexual activity with Ms Higgins, claims he was able to be identified as the alleged rapist despite not being named at the time.

On the witness stand last week, he was grilled about a large number of text messages he sent during a lengthy meeting with solicitor Warwick Korn on the night Ms Higgins' claims first made headlines.

These included Mr Lehrmann texting his then-girlfriend about the advice he said Mr Korn had provided.

"If I am named tonight then he says I'm up for millions as defamation," Mr Lehrmann told Greta Sinclair in one message.

During his evidence, Mr Lehrmann claimed he had "fabricated" this, and other comments from Mr Korn, because "Rome was burning and I was trying to put on a brave face" for the "distraught" Ms Sinclair.

On Thursday, during submissions about whether the court should grant Mr Lehrmann's application for an extension of the 12-month period in which to sue for defamation, Ten's barrister raised the messages.

Matthew Collins KC said it would be "quite extraordinary" if Mr Lehrmann, who had just learned he was the subject of rape claims, had the capacity to "put words in a lawyer's mouth" on the night of the texts.

He pointed out that Mr Lehrmann had been firing off the messages during a six-hour meeting with Mr Korn, which had apparently also involved watching The Project, texting multiple friends, and drinking scotch.

Dr Collins described some of Mr Korn's purported comments, including the "up for millions" statement, as "something a lawyer would say", suggesting the solicitor had indeed made that remark.

"It's inherently unbelievable," Dr Collins said of Mr Lehrmann's claim of having invented the advice.

Earlier, Mr Lehrmann's counsel told the court one of the parties had, in written submissions, made the "unfair" assertion the 27-year-old would have to be "a habitual liar" for his evidence to be accepted.

Pushing for an extension of time after Mr Lehrmann waited nearly two years to launch defamation claims, Matthew Richardson SC argued it would have been unreasonable for him to do so sooner.

His reasons included that Mr Lehrmann may have been required for cross-examination before the start of his criminal trial, at which the 27-year-old maintained his right to silence.

Any answers Mr Lehrmann gave in a defamation case might have been "exploited by the prosecuting authorities" at the criminal trial, Mr Richardson said, creating unfair prejudice.

Mr Lehrmann was not charged until August 2021, midway through the 12-month limitation period, but Mr Richardson rubbished suggestions there had been an "open window" in which to sue between the allegedly defamatory publications and the criminal charge being laid.

"So what?" Mr Richardson asked..

While there was no criminal case on foot for about six months after Mr Lehrmann alleges he was defamed, Mr Richardson argued the possibility of prosecution had always loomed large.

In support of this point, he cited the fact police had publicly stated there was an open investigation three days after Ms Higgins went public with her allegations.

There was then an announcement that a team of five investigators was working on the case, a police interview with Mr Lehrmann, and regular coverage centred on the preparation of a brief of evidence.

Mr Lehrmann pleaded not guilty to a charge of sexual intercourse without consent, which was dropped after juror misconduct forced the abortion of his eventual criminal trial.

Also at Thursday's preliminary defamation hearing, where each respondent said Mr Lehrmann's lawsuits should be thrown out, Ms Wilkinson's barrister, Sue Chrysanthou SC, argued extensions of time were only for "unusual" cases.

Ms Chrysanthou rebutted Mr Lehrmann's argument that the criminal case had made it unreasonable for him to sue within the limitation period, citing a number of other high-profile matters.

These included one of her former clients, NRL star Jack De Belin, who sued for defamation on the final day of his 12-month limitation period despite the existence of a criminal case against him at the time.

"What's the point [of taking longer] if you're going to let your reputation suffer?" Ms Chrysanthou asked.

Barrister Renee Enbom KC, representing News Life Media and Ms Maiden, told the court there was "a significant gap in the evidence" when it came to Mr Lehrmann's reasons for not suing on time.

Ms Enbom said the reasons he gave last week, including a lack of access to funds, were all focused on his situation in March 2021, with no explanation about what was happening at all other stages.

Justice Michael Lee ultimately reserved his decision on whether to grant an extension of time, saying he would give it as soon as possible.

If Mr Lehrmann gets an extension of time, all four respondents have indicated they will argue they were justified in publishing what they did because, according to them, Ms Higgins' rape allegations were true.

Ms Chrysanthou told the court a full defamation trial, if required, would likely run for four weeks.