Pom: Your assumption with regard to a change of frequency cancelling a previous restriction is potentially a VERY dangerous one!!
Of course we are supposed to say: 'Report your heading/speed/cleared level (or whatever) to XXX' but sometimes we forget. In addition our manuals say that we can coordinate restrictions between controllers by phone, and you will of course not know this.
I would suggest that you should continue on the heading/speed etc and check with the next controller whether you are released.
As is the usual response to all these sort of questions: IF YOU ARE NOT SURE, ASK!
Hippy: Short answer to 'No speed restrictions' : your first option.
Yes, I would hope that all pilots who fly in any airspace are aware of the limitations and regulations pertaining to it. It is the same as knowing your own, the aircraft or the airfield minima for an approach and which applies in which case. Unfortunately, the cases to which I referred in my last post are often foreign pilots specifically asking for high speed clearance below FL100 in Class G. The response I mentioned in that post is usually met by a somewhat non-plussed: "Roger"
Standard Departure: Yes, spot on IMO.