Shallow Clone using --shallow-since

Would it be possible to enhance Shallow Cloning so that it supports --shallow-since arguments. Specifying the depth in absolute terms is a very clunky tool, some projects have many commits a day, others hardly change in 6 months. Git has a feature where you can fetch all changes since a date. It shouldn't be too hard to include this in the CI scripts as an option.

The ideal would be to have this as a relative date, but that's slightly more work since git doesn't support it natively.

Is this a feature you'd be willing to consider?

~"feature proposal"