Vines which become disconnected from a block all break at the same time

The bug

Vines without a supporting block all break at the same time when the supporting block is broken.

To reproduce

1. Run the following commands:

   /setblock ~1 ~20 ~2 minecraft:stone
   /fill ~1 ~ ~1 ~1 ~20 ~1 minecraft:vine[south=true]

2. Break the stone

Expected behavior

One would expect, in line with the way sugarcane and kelp break, that the breaking would spread from the top down gradually.

Observed behavior

All blocks break at exactly the same time.