[cc-community] Relicensing after publication

[Per Starbäck]

At https://creativecommons.org/faq/ and other places is advice on how
to apply CC licenses to material you are publishing.

I would like to see help also on how to apply CC licenses after the
fact; how to best tell the world that you henceforth allow
distribution of some of your works according to a specific license
even when not making a new release of the works. (Note: I'm not
currently looking for help in how to do this myself. Rather I'd like
to see what thoughts others have on this, and that it hopefully will
lead to a solution for others looking for such help.)

I think this is something that could be a rather popular if it was
easy and clear how to do it. But to republish the work yourself will
often be seen as much too much trouble, in particular if it is
material you don't have digital versions of. That is not practical for
uses such as "I release all books I've published before 1980 with
CC-BY".

I think of this as signing a document stating three parts:

1. what works is it about
2. what license
3. from when does it apply

I think common answers for those are:
1. everything / everything published before a particular time / only
works of a specific kind, like photographs, short stories, ...
3. from the date signed / from my death / x years after my death

I'm guessing that many people who normally wouldn't consider using a
CC license still think that copyright terms are much too long and
would prefer to relicense when they see no commercial benefits in
having it otherwise anymore, either because they are thinking of what
happens when there are gone, or because they are thinking of stuff
they've published decades ago.

Is that sensible? What would you do with that signed document then?
What help can we give?