If you restrict the access so that only a subset of students can see the Assignment then only those students will be shown in the submissions page. If you think about it this is mostly sensible. There's no point showing (possibly) hundreds of students who could never submit.
However - and I've been caught by this too - it is possible to add a restriction that masks submissions already made. Which is less understandable.
It's maybe a bug... or at least a feature worthy of different opinions. You could raise a report in the tracker
However - and I've been caught by this too - it is possible to add a restriction that masks submissions already made. Which is less understandable.
It's maybe a bug... or at least a feature worthy of different opinions. You could raise a report in the tracker
In general, Assignment is sensitive to configuration changes made *after* submissions have started. It turns out that's mostly a bad idea.