When you finish a job across multiple batches, per-unit costs can drift between them—the first batch arrives at one cost, the next at another, and the same part lands in inventory at two different values even though it all came from the same job. A new Job Settings option, Average Cost Across Batched Receipts, solves this by evening out the cost across every batch of that item so each unit carries the same average—even correcting earlier batches that have already been picked.
The setting lives under Roll Forward Job Cost Changes and only works when that option is turned on. It's all-or-nothing: if any of the item's receipts fall outside your Inventory Adjustment Cutoff, Fulcrum leaves the entire set alone. It's off by default.