According to a very trusted source, Apple Store employees who have been tasked with improving Apple’s new mapping service are using Bing Maps to correct reported address errors in Apple Maps. According to my source:
When someone has reported an [address-related] problem, they look up the real address on Bing (via an embedded map on the page) and then correct the location.
Using a different service to fix the problem is not surprising, but skipping over Google, the clear industry leader in mapping, due to their disdain for the company, is the same issue that got them into this mess in the first place. Remember, Apple had a year left on its Google Maps/iOS contract.