Depends where you are. Someone needs to inform some of these colleges that the 90 day rule exists, they often program resit exams for the same module at less than 90 days. Come audit time they will be up sh!t creek if they allowed any of their external students to sit, another finding for them. If I was you, I'd use that calendar well and don't tempt less than 90 days, it will only lead to disappointment.how strict is the 90 day rule?
As far as I know it applies only to the module you have failed.
The extra tuition given by colleges on the subject to get around the 90 day rule is often a little 'light'.