The answer is easy, it was given in your link to the NASA website:
When we designed and tested Ingenuity on Earth, we expected
Ingenuity’s five-flight mission to be completed within the first few
months after Perseverance’s landing in February 2021. We therefore
prepared for flights at atmospheric densities between 0.0145 and
0.0185 kg/m3, which is ...
In some sense, it already is.
Ingenuity was designed for 5 short test hops during the first 30 days. Pretty much every flight since then was higher, farther, and longer than originally designed and planned, in addition to the helicopter only being planned to operate for 5 flights and only for 30 days.
When the helicopter is done being "useful"
NASA has a webpage with an interactive map of the rover and helicopter. As of today,
the helicopter is slightly farther (straight-line distance) from the landing site than the rover.
the rover and helicopter are about 400 m apart.
Of course, the answers will change as the mission progresses.
The deployment system for Ingenuity was designed and manufactured by Lockheed-Martin. The steps are described on this webpage:
Perseverance lands and searches for an acceptable airfield.
The debris shield cover is released and dropped.
The rover drives to the center of the airfield.
The deployment system is unlocked.
The helicopter is rotated to vertical. ...