It is closely related to Ichang papeda, but it is not as hardy as Ichang papeda.
Here's an excerpt from an old article:
" This species [Ichang papeda] is cultivated in the vicinity of Ichang, and it bears a very large lemonlike fruit that is of sufficiently good quality to cause it to be shipped to markets several hundred miles distant.
In China this species occurs in an undoubted wild state in the hills of the Upper Yangtze Valley from Ichang west and southwest in Hupeh, Szechwan, and Kwichow, growing at altitudes of 1,500 to 6,000 feet. In Assam a closely related but slightly different form is found at an altitude of 5,000 to 6,000 feet in the Khasi Hills.
The species thus ranges over a region at least 1,500 miles long and some 500 miles wide. "
Journal of Agricultural Research, Department of Agriculture, Volume 1, Washington D.C., October 10, 1913
Citrus ichangensis, A promising, hardy, new species from Southwestern China and Assam, article by Walter T. Swingle
Apparently the natives in that area used the fruits as a form of insect repellent for their feet.
Most sources say the fruit is otherwise not used by the locals, but I do recall seeing one source that described a few culinary uses.
I would gather then that the fruits are/were probably not often used, but might have been used occasionally by some native tribes in some locations. Probably not great fruit quality.
In another study I saw, the fruits of Khasi papeda do not contain high levels of photosensitizing furanocoumarins like lime and lemon do, and the levels were lower than grapefruit.
That Khasi papeda would have a lime-like flavor is not surprising, because Khasi papeda is also related to (and its native growing range is not that far from) C. micrantha, which is basically the ancestor of limes (and has off-the-charts high levels of furanocoumarins, by the way).