My 2003 MX Pro Coils took ages to free up, I guess about 100 miles or so. The following helped.
Minimum air in the preload chamber (right leg)- that is, lots of sag. Got them moving over the full travel more often.
Big undulations, or popping the front off drops to go through the full travel more often.
Avoiding road work, even if that means going up and down the same trails!!
Now they are there, they are great!!