This may seem like an odd question, but is there anything involved with the recent changes you made to I-73 Future Madison and I-840 Future --> I-840 around Greensboro that would cause someone's numbers to drop? Possibly some road mileage was being double counted and it no longer is.
The change to I-73 Future Madison fixed the concurrency between I-73 Future Madison and US 220. Before the fix, if you had both routes clinched, the segment between US 311/220 Bus and NC 65 was counted twice. Now, it is correctly counted once. This reduces overage mileage in NC to drop by the length of that segment.