If he doesn’t get a chance to arrange, say, for messages to be sent out in the event of his death or incapacitation, then his best bet might be to tell them, but if it looks like he can get away with it it might be better for him to imply that he’s already told some people, but not reveal who. That way they will conclude they can no longer rely on dementors, but the secret doesn’t actually escape.
He did already give Hermione that letter which she could use to find out the secret, but it’s probably too late for her to make any use of it. It would have been a good idea for her to read it as soon as she was told that she was accused of murder, except she probably never had the chance to do that, and anyway she won’t have a wand in Azkaban.
If he doesn’t get a chance to arrange, say, for messages to be sent out in the event of his death or incapacitation, then his best bet might be to tell them, but if it looks like he can get away with it it might be better for him to imply that he’s already told some people, but not reveal who. That way they will conclude they can no longer rely on dementors, but the secret doesn’t actually escape.
He did already give Hermione that letter which she could use to find out the secret, but it’s probably too late for her to make any use of it. It would have been a good idea for her to read it as soon as she was told that she was accused of murder, except she probably never had the chance to do that, and anyway she won’t have a wand in Azkaban.