because i got bad anxiety in about April, mostly due to the HSC, my doctor recommended me to stay off caffeine so I could sleep better. However, due to the absolute pain and suffering that was Term 2&3 with major works, exams and assignments I was basically surviving on about 7 cups of tea per day so I could get through all my work.
In the holidays (after graduation) I limited myself to about 2 cups of tea per day and no caffeine after 4 pm, it was VERY weird to get used to because my body felt tired and energetic at random times. But after about a week it all calmed down and I slept better.
So, if your body is dependent on caffeine, my advice is not to stop in the middle of the HSC, it screws with your energy.