^ Great point ^ Any detectable level of ammonia is unhealthy for fish...
Something to keep in mind. As long as there is more ammonia in the water than the current bacterial colony can consume, will trigger an expansion in the bacterial colony
So whether you have .01ppm, or 3 ppm, the bacterial colony will be growing
Therefore I suggest you do what changes to keep the detectable ammonia as low as possible, and I suggest that as long as you have a reading at all, your bacterial colony will be triggered to expand
thus doing water changes will not slow down your cycle.
This is another place where more is better does not apply
The ammonia reading being higher does not equal faster growth in quantity of bacteria