This is supposedly true at airports with operating control towers. Kind of depends on if the controllers remembered to throw the switch. At uncontrolled fields, it doesn't mean much, if anything.
A reference for the approach question would be the approach plate itself. The minimums for the approach are listed and any changes to those minimums in the event a portion of the approach lighting is inop. I've never heard of an airport beacon being required for anything. I've alwas just considered it a nice to have, but I have no reference to that.