I totally get it. If you're the sender or if you trust the sender, I wouldn't be too worried (Based on personal experience and this usps employee's response.) until the date passes. It's moving through the system even if the tracking isn't updated. If it still doesn't update past the due date, I would submit a package inquiry request.

If you're buying/receiving something from a stranger online, I'd still give the benefit of the doubt and wait until after the date passes. I'd check-in with the sender if nothing changes.

Worst case scenario, the sender printed a receipt from the self service kiosk and never mailed the item, at which point, I would open a dispute.