Perhaps the solution is a monthly "NOOP" release?
If, however, I saw a statement at the top of the README that said:
"Update as of 2 months ago: We believe this project to be complete. We are not adding new features at this time, but if you see any issues, please open a ticket, as this project is still under active development as needed"
then I would feel very confident.
I personally support every version of my projects.
My goal is not to minimize the effort to myself but to facilitate the use of my software.