License in Deep Horizons contain a solution:
I would like to suggest for all authors to include something similar clause if not use CC BY-NC-SA 3 which allow modify (but -ND version not). Without this the situation will be worse due to new OXPers tends to copy licenses from famous authors and the problem will spread.The "Dead Man's Switch" Clause: If the Author is unresponsive to communication attempts through the official Oolite forums (currently located at http://aegidian.org/bb/ at the time of this writing), via email (.....@.....), and all other reasonable attempts at communication for a period of 6 months following the final communication attempt, this OXP will transition to Creative Commons Attribution-NonCommercial-ShareAlike 2.0 US License and all rights and priviledges are awarded accordingly. [...]
The "Dead Man's Switch" Clause within this license automatically and immediately becomes activated upon death of the Author provided that this OXP is not superseded by a later released revision.
The "Dead Man's Switch" Clause within this license will only apply if this OXP is not superseded by a later released revision.
What do you think?