INCIAR (Create Intercompany AR Invoices) is not picking up all orders immediately

We have the INCIAR (Create Intercompany AR Invoices) concurrent program scheduled to run every 10th minutes by the concurrent manager in order to have a fast and smooth execution of our internal sales orders. This process has until recently run smoothly and fast with a max. 30 minute delay from ship confirming the delivery for the internal sales order until the related intercompany AR invoice is generated and present in Receivables.

For the last 14 days we have experienced that the INCIAR (Create Intercompany AR Invoices) program has not picked up material transaction in mtl_material_transactions table related to internal sales orders , which in our opinion are ready for invoicing - invoiced_flag = 'N' and costed_flag + movement_id IS NULL - without a significant delay - sometimes up to 20 hours.