Well, depends which acts of heroism it is you're talking about.
It's looking like he's playing a civilian with a boat going to help out in the evacuation - I wasn't aware there was an age limit for those people?
Sorry I thought you were referring to the naval rating I described in my previous post. Of course he could well be the right age for a civilian boat owner - plenty of men that age took part in the rescue.
Both of Rylance's grandfathers were POWs of the Japanese, and this maybe has led to his very strong pacifist views. Nothing wrong with that, but I am less impressed with his patronage of the Stop the War Coalition, which seems to exist to protest against all wars, except those where Russia is involved.
Not a bad actor, though.