By default, you have to click on refresh button (F5) to get the updated list of transport request in the import queue, STMS. There is a way that you can get the updated import queue by periodically schedule the import queue job in the background.
Go to transaction code STMS and click on Import Overview (F5). Click on Extras and select Update All Import Queues.
Choose At Start Time and Period from the selection list. SAP recommend to select Daily. Press Enter to proceed.
You will received a message status, Background job scheduled..
