Signage for End of Passing Lanes

[Bitmapped]

Most states I've traveled to treat the end of a passing or climbing lane like the end of any other lane, with a sequence of Lane Ends-type signs.

I've noticed Virginia tends to do things differently when passing lanes end, at least on their older 3-lane routes like parts of US 1 and US 11. I've seen some cases with a "No Passing Zone" or "Do Not Pass" sign at the end of lane. I've also seen cases with no signage at all, just the double-yellow line tapering over. Does anyone know why VDOT does this? It doesn't seem like it would be MUTCD-compliant or wise from a safety perspective.