Phillip on todays show confessed the one and only time he pulled a sickie was the time when it snowed and Fern had to present on her own. He confessed that he could have got in if he tried but decided to have a day in the snow with his family. He also said that Fern was not impressed with him at the time for it.
He also got the date very wrong. He said it was in 2011 when Fern had left many years before then. I believe it was a few days before this clip in 2009:
January 9th 1989 - December 3rd 2006