Here is some good gen I received recently.
from Hong Kong Air Traffic Management standards section.
FL 130 at MELON/MANGO
Q: When initially cleared to be FL 130 at MELON/MANGO, then approaching these points ATC clears the aircraft to an altitude, do I still have to adhere to the FL 130 restriction?
A: No. Clearance to an altitude cancels previous restrictions, unless specifically stated otherwise by ATC.
8000FT at TD/TH
Q: When on approach to RWY 25, do I have to cross TD/TH at 8000FT?
A: No. This is a procedural restriction only, ATC clearance to an altitude lower than 8000FT automatically cancels this restriction.
SPEED CONTROL
Q 1: When ATC clears you for high speed through MELON/MANGO, does the 250KTS below FL110 still apply?
A 1: No. The high speed clearance applies until further advised by ATC.
Q 2: When cleared high speed do the final approach speed controls still apply?
A 2: Yes. As at any busy airport, strict adherence to final approach speed controls is essential, to allow ATC to maximize runway usage.
This is the stuff I like to find out from ATC, so looking forward to an informal beer!