How old is Toast supposed to be?

He seems to be around 50, and in one episode tells Jane he's been acting for 28 years, which would be about right if he graduated from drama school in his early 20s. However in one episode he is shown as a young actor during the time of the moon landings in 1969 - even if he was only 18 that would still make him in his 60s. I seem to recall an interview with the writers who said although 'Toast' was set in the modern day, it was really meant to have a 70s/80s feel (hence all the old actors appearing from that time, like Peter Davison, John Nettles etc). So perhaps Toast is a sort of 'ageless' character, like Sherlock Holmes.