Some schools have tried to minimise swapping between class groups within a year, by using, say, 4 bands. i.e the students in 7A, 7B, 7C ,7D. This means that if due to COVID they can only have a quarter of the year group in at a time they can invite bands into school across the week and they follow their set timetable. Its a bit more of a faff to prepare, but I think will save a world of pain as we begin to open fully as the year progresses.