The actor Richard Todd [who played Gibson in the film] was interviewed this aft on BBC R5, he sounds barely half his 88 years. He was full of praise and admiration for those that took part in the raid, and spoke of his regret that he had never actually met any of them, 'I was elsewhere' he said dismissively.
Minutes after the interview ended the studio was receiving numerous messages explaining just where 'elsewhere' was. The consensus being that Todd was probably training for his forthcoming drop by parachute into occupied France, as later portrayed in the film The Longest Day.