Since the settlement owners would instigate the second attack to reclaim their settlement, technically FACTION 1 is not breaking rule 14.1:
as they did not "attack" the settlement the second time, they were actually the victim of an attack after their victory over FACTION 2.
It does raise the question of should FACTION 2 be attacking the group so soon after being defeated by them, given rule 9.1:
Since FACTION 1 has remained in the settlement for the duration of the two hours, technically it is the same situation, meaning the settlement owners would (in my opinion) be violating this section of the NLR rule. They would also technically be violating rule 9.2:
That's my take on it at least. Interesting question!