Attorneys fighting on behalf of Bill Cosby have been scrambling to deal with shifting evidence in the comedian’s civil trial over allegations that he sexually assaulted a teenage girl at the Playboy mansion nearly 50 years ago.

Judy Huth said in a recent court filing that she now believes the assault happened in 1975 when she was 16, not in 1974 when she was 15 as she had long alleged, spurring cries of foul and a request to dismiss the case from Cosby’s attorneys, who said the change had upended their defense on the eve of trial.

“It’s not fair,” Cosby’s lawyer Jennifer Bonjean said outside court. “It’s called trial by ambush.”

According to Associated Press, Los Angeles County Superior Court Judge Craig Karlan gave no indication he planned to throw out the 8-year-old case just before a trial that he is determined to have started as scheduled on Monday and forged ahead in preparations.

And with Huth’s attorneys citing the change in her story, they said that it comes after research of archival evidence led them to determine the dates around when Cosby was shooting the movie Let’s Do It Again at a Los Angeles-area park. 

Huth says that the two met before he took her to the mansion.

Evidence includes a dated photo of Cosby with a beard and a tuxedo looking exactly as Huth had remembered him.

Cosby’s attorneys have built much of their trial defense around the timing of the trip to the Playboy Mansion, including going to great lengths to establish the comic’s whereabouts at the time and basing their planned questions for Huth on the witness stand around her account of the chronology.

In her lawsuit, she alleges that Cosby forced her to perform a sex act on him in a bedroom of Playboy founder Hugh Hefner’s famed Los Angeles mansion. Bonjean acknowledges that Cosby met Huth, as a photograph shows that the two were together, but says that the visit happened later when Huth was not a minor and that no sexual assault took place regardless.

“It’s extraordinarily difficult to defend against an allegation from 50 years ago. Nobody could do it, innocent, guilty, or something in between,” Bonjean, who also represented Cosby in his criminal case and is representing R. Kelly in his Chicago child pornography trial, said outside court. “You work to create a defense, and then all of a sudden, at the last minute, it’s a bait-and-switch.”

Huth’s attorney Gloria Allred declined to comment outside court.

Meanwhile, Bill Cosby gave a videotaped deposition early in the case but will not be required to testify during the trial. 

“Mr. Cosby is a guy who has never settled for anything in life, and he’s not going to settle in this case,” Cosby spokesman Andrew Wyatt said after the