Is there a term for a pre-made message, intended to boost morale, released to the public by a leader that, at the time of the message's release, is dead/deep in a bunker/surrounded by the enemy? Can you name any examples from history?
Boris Johnson is to send everyone a letter by post. He was diagnosed with covid-19 a few days ago so is likely to be in the throes of the virus when the letters arrive.
Given that he probably won't be in a state to speak to the public in a few days time, it seems to me that this mailshot has been designed to be a proxy. I think I've heard of examples of this kind of thing before. I have a feeling that Churchill prepared something to be read in the event of a Nazi invasion. Maybe it's just a cinematic trope.
Is this a thing? Is there a name for it? Can you name any examples in history?