That looks like a machining error. They probably didn’t recalibrate the CNC machine for tolerances between batches. But I think the consequence is that there is extra wood around the lock mortise. If you were ever intending on refinishing the stock I would use a round scraper and level out the area. Not the worst mistake I’ve seen from pedersoli.
Their CNC tolerances are generally higher, which is a reason why many of their stocks are bulky, for example their 1766 Charleville has about 1lb of extra wood on it in the. Wrist and forearm.