If you can afford it financially, the best lectures and
tutorials are always from private tuition. Doesn't mean all private
tuitions are of good quality, but those that are of great quality,
are better than the lectures and tutorials in schools.
Just saying, in case it turns out you're not allowed to change JCs,
but are still are unhappy with the lectures and tutorials from the
school you're stuck in, you can consider private tuition (if you
can afford it). Just pointing out alternative options.