Originally Posted by
EMAW
But the original question was what if you are given an early descent, well outside of the arrival?
The original question doesn't ask that.
In fact, the original question states that the example aircraft is arriving in cruise at 300 knots, and has not yet begun a descent.
The first published speed restriction is at EEEZI.
Again, the wise pilot will query ATC, and in fact, if any question exists, is required to query ATC.
If ATC desires a speed restriction prior to EEEZI, ATC is responsible to issue that restriction. In lieu of an ATC clearance to the contrary, the pilot is not responsible for a speed reduction prior to EEEZI.