The router allows a smaller network (the /29) which has 5 'useable' addresses. Shrug.
Overall, this suggests that there's a "feature" in the Hub2. Which sort-of suggests that testing of the s/w may have been somewhat done differently.
Whether this 'feature' is otherwise useable remains to be discovered.
Perhaps the simplest solution is for the Hub2 s/w to be 'upgraded' so that it doesn't provide subnetting? That removes the anomalies at a stroke.
Counterpoint. Of course, every home network has 253 devices operating on it. And every (home) network has devices which should (by default) all be connected to the wider internet.
