Sometimes when I'm nto in Sanctuary, my Pip-Boy workshop status screen will show it having 0 beds, even though it has plenty. When I return to it, the build screen and the pip boy will show the correct number.
Also, every settlement I have, when viewed from the pip boy, has an alert next to the defense rating, no matter the number. When viewed from the workshop, the defense rating will turn green when adequate, but the alert never goes away in the Pip-Boy.