What is SY?
My sister had a problem, bed wetting came back but it turned out to be partially caused by some inflamed kidneys possibly, i can't remember now? but mostly was improved by self control.
She also struggled at school, my mum had to explain the problem to the teacher.
No drinks at bedtime, toilet before bed as you said, and possibly wake up for toilet at 11pm?
My sister got a gold star sticker chart and a treat at the weekend for first 1 then increasing numbers of dry nights.