I created a shipment last weekend, and then I created a FedEx label and entered its tracking number. The package shipped, and was delivered today. Delivery window was from Tuesday to next Monday so it was delivered in time.
On Seller Central, the tracking number still appears as "Confirming...". The same tracking number works on FedEx's website, so it is the correct number. In the past, when I had issues like this, going to the "Track Shipment" tab on "Shipment Summary" seemed to refresh its status but for some reason it's not working this time.
Are there any consequences of this? Will the system tag it as not delivered in time window or something like that? Is there a way to make the tracking actually work and get the delivered status from FedEx? As I said it is the correct number and tracking with that number on FedEx's website works.
Honestly, I wouldn't worry about the tracking on an inbound FBA shipment right now. Amazon is known for not having up to date tracking information. Now, you wait until the warehouse gets to your box. Hint: it's going to be more than a couple of days.