Extending the SP Dynamic Metadata Provider

[Cantor, Scott]

> It checks at run time, but AFAICS only as part of the filter operation
> (assuming that the ValidUntilFilter is configured).

That's a separate check. That's for limiting the validity window.

>  But I would be the first to say that I don't completely 'get' this code so whether
> the edge case behavior is the same I couldn't comment.

I'm pretty sure the actual validity check happens every time it returns a piece of metadata from resolve()

-- Scott