Different aged siblings in the same class at Junior school?

[PersonIrresponsible]

My sibling is exactly two years older than I, yet, we were supposedly in the same class when in Junior school. Yy

Was this ever an official policy in early/mid 1980s. Or is there a reason for it ?

I went to a tiny school, just 2 classes: one class for infants, one for juniors.

My daughters friend attends a primary school where there are mixed years. She is in year 3 but her class is made up of year 3's and 4's.

I went to private secondary school in the 80s. You could take the entrance exam in year 5 and join the new year 7 intake. I was one of the oldest in my year, my best friend was 20 months younger than me and was closer to my sister in age with only 3 months between them.

Continues to be normal in rural areas.

In our school Pre-school and reception are one class, Y1 and Y2 are one class,
Y3 and Y4 one class and Y5 and Y6 are one class.

most years have about 10 children in on average so 20 per class. Most schools round here are roughly the same. Our next nearest school only has 35 in the whole school and they are split over two classes and share a head with another small school locally.

At our primary school myself and a few other autumn birthday kids had to skip ( what we now call)year 2 and spend two years in what we call year 3 because the year group was too big or something.

I went to five different primary schools but the one I was thinking about had me and a brother, who was two years above me, in the same class.

It was a well populated school so I'm assuming it was a policy. We were only there for a short time before we got removed so I was trying to make sense of it.

Thanks everyone for their input.

My primary had vertically grouped classes (late 80s to mid 90s). Years 1,2,3 and 4,5,6 together. There were 3 classes of each banding so it was clearly a conscious decision, and it was combined with whole topic learning. It worked well IME. We were split to different tables for maths but everything else was done as a class. I don't remember siblings ever being placed together though, they must have been put in different classes. This was Oxfordshire if that's any help? (It wouldn't surprise me if it was an area-specific 'fashion').
DC's school currently has a combined yr5/6 class as they don't have enough DCs for 2 classes.

It might be that your brother was behind academically (because of the moving around) so they moved him down a class which just happened to be yours?