When does a film become "period" in Australia?

A long-standing mate who runs a TV production company in Australia is passing through London this week and we caught up for lunch today. In addition to selling his programmes, he is looking for small-budget films to make. I gently suggested that he might be interested in Blind Mike, a music-laden screenplay that I had written, inspired by Grantley Dee, the famous Australian pop singer  and the world's first blind DJ. He couldn't remember Grantley and in any case, "we don't have a market for period films". "What do you mean 'period films'?" I responded with some astonishment, "this was in the 1960s!"  "But that was last century, mate!" he said dismissively.