[Par71]

Snap = as late as possible
Full Sweep = as early as possible
Random Sweep = anywhere in between

Non-Automatic Snap Release is just the latest Release than can still be deliberately triggered.

It has an earlier Release Point than Automatic Snap Release (because you have to trigger Release by a deliberate maneuver before an Automatic Release occurs). But it is the latest Release Point for the Non-Automatic Releases (the far end of the spectrum of possible Non-Automatic Release Points).