SQA higher question, about tutors?

I've just began 4th year and I'm all credit except maths. I had a careers appointment and they told me I need higher maths at an A for one sitting - to get into the UNI course I want - meaning I can't take int 2 in 5th year and higher in 6th year. So I was wondering if I had a private tutor all through 5th year learning int 2 and higher maths and then literally take the subject in 6th year. Would that count as one sitting? Would that even be possible?