A MTO manufacturing batch can be processed anytime before the sales order is processed into an invoice. Right-click on the detail line of the sales order and select Process Manufacturing Batch from the context menu to process the batch.
The batch can also be processed from within the manufacturing batch. Review the Manufacturing > Processing Batch section for more details on processing a batch from within the manufacturing window.
An MTO Manufacturing Batch will be automatically processed when the sales order is processed into an invoice since the MTO batch must be processed before the sales order.