6 Red Snooker penalty

[vernongene]

The rule in 6 Red Snooker is: "A player cannot snooker behind a nominated colour at any time"
The scenario is: Play A nominated the black (after potting a Red), misses the pot and the Black ends up snookering
the remaining Red/s.
The question is: What is the value of the foul? Is it 4 (the ball on) or 7 (the snookering ball)

Also, if just the Pink and Black remain as in Section 3 Rule 12 B) (ii) snookering is permitted.
In 6 Red Snooker is this now not allowed?

[Londonlad147]

First question: you are snookering behind a nominated ball so the penalty is the value of the ball on (ie black in this case), so seven points. The ball on is the black because we're talking about the offender's turn: he can't snooker behind his nominated colour. If he does, then he is penalised according to his ball on, not the ball on for the incoming player.

Since no exceptions are listed, I assume the 'when only pink and black remain' exception is not valid.

[vernongene]

All cleared up.
Thank you for your reply