If however, there was another restricted area above (based at 2,500) and it was also active, and controlled by the same authority, then no, you would not be able to fly through at A025.
Another good clarificaiton point on this would be Moorabbin Class D. Goes up to 4,500ft and on top of that is Class C from 4,500ft upwards. You can't sneak between the two
Probably the best way to decribe the
documented airspace level is that they are "not inclusive." So therefore, 2,500ft is not included in the airspace and hence 8,500 ft is not included either.