Making a Save on a 1 & Unit Coherency

Good Morning / Evening!

The following 2 situations have come up a few times in previous battles and would appreciate some clarification.

1.Model A, with a range value of 3, is attacking Model B, which has a RtN of 6.

The combat solution has been decided, giving Model B a +2 Defensive CS bonus.

Model A rolls a 3, achieving a hit with a CRN of 6.

Model B now needs to make their save and their total bonuses, including Toughness(2), Armor(2), and CS(2), equal 6. This means that even on a roll of a 1, Model B cannot fail this save.

The question I had is does the “Impossible Attack” rule apply here?

As written, it seems that making an impossible attack is only applicable when the target’s RtN or MtN is too high before the attack is made.

The reason I question this is the inclusion of the line “or their combat Solution bonus is significant,” which made me think that it could be applied in situations where you could hit a model, but the model could not fail the save, meaning they would still fail their save on a 1.

2. Concerning model coherency. Does every model need to be within 2” of at least one other model belonging to the squad, or do they need to be within 2” of every other model of the squad at all times?

Thanks in advance and apologies in advance if I have overlooked something simple.