The goal is to insulate a code base from potential problems with new port upgrades.
So maybe if a port upgrade outdated command can be amended not to use the freshest of the fresh ports, you can avoid tracking down errors in ports affecting your code.
As far as I see, port info port_name doesn't have any extra release date options:
$ port help info
Usage: info --category --categories --depends_fetch --depends_extract --depends_build --depends_lib
--depends_run --depends --description --epoch --fullname --heading --homepage --index --license --line
--long_description --maintainer --maintainers --name --platform --platforms --portdir --pretty
--replaced_by --revision --subports --variant --variants --version
I suppose the best alternative to this is to perform daily incremental upgrades. Then when something breaks, it's easier to rollback since likely only a few ports will change per day.