This is a feature I have discussed directly with our account team but worth capturing here as well for wider input.

Currently in Registration Manager > Report tab, the pupil filters do not include the ability to filter by pupils on particular registers as defined within the Student Registers module (for instance Pupil Premium). The ability to report attendance particularly for these vulnerable groups is essential. We are currently working around this by creating a separate 'custom group' which can be used as a filter, however, this is not synced to the actual pupil register and is therefore prone to error and creates additional workload.

There is a filter for SEN which I believe links back through the deprecated SEN Manager module through to the SEN register within Student Registers, so it would appear this functionality is feasible within the wider system.