If an activity can have overrides e.g. due dates etc. then these can be set on a user or group level.

It should be possible that overrides are also possible when groupings of groups are used.

An example can be seen in screenshot. The course uses "meta groups" like 'Members of groups A to E', 'Members of groups G to K' etc. These groups are only necessary for the override but would otherwise handled via groupings. The discrepancies of the numbers is that in the single letter groups only students are member of, while the meta groups also contain teachers.