Do you know how sets are determined at your school?

[SecondaryBefuddled]

In the old days at the end of the year you sat a test and the score for that categorically determined what set you went into for the next year.
To be honest that is how I thought it worked now as well, but I've been advised that there are smaller tests during the whole year and these count too, but are not given a timetable (afaik) for when these tests occur, what weighting they hold or what they will cover. Is it unreasonable for me as a parent to expect that information to be made available/clear to myself or my dc? If you think it is, please could you explain what the downside of it would be? What does your school do?

You seem very bothered by the setting. Let your child deal with it.

In some schools the sets are tied to another subject. For example, I teach geography but we are in a timetable block with English so as a core subjec they get to decide the setting and we have to put up with it. It has been with other subjects too. Every school does it differently but if your child excells in one subject it might be that subject doesn't get the deciding vote on the setting.

getting one of the highest marks in the exams in the whole year and excellent feedback from that years teacher about how their work is beyond expected for their class throughout the year.

If they're doing this well, why would you want to move them? They might not gel as well with the teacher in another set.

Setting does not determine final outcome. I've known kids outperform those 4 sets higher.

Lots of mini tests and assessments

They may not have done the same exam so a 'high' mark may not mean he is one of the best in the year, just one of the best at that level.

I’m a secondary teacher of a core subject and in our school, subjects with untiered entry (i.e. no Foundation or Higher- just one exam for all) are taught as mixed ability, and we like to shuffle the groups about every year until GCSE where the class is pretty much fixed unless there’s a severe behaviour issue. We use SATs and any other Year 7 baseline tests to work out opportunities for intervention and TA support. We do assessments throughout the year and end of year exams to track progress and identify gaps.

DS's school have mixed sets across all year groups!