Don't trust Amazon's 2 day delivery Locked

I placed an order for an 18-135 STM lens from Amazon on Saturday, using the free 2nd day option with Prime, for delivery today (Monday). I did have the option of "overnight" for $4, but with the Sunday in between that would have also been today.

This morning, it showed the shipment underway, with delivery by 8pm. As the day went on, the status bar moved, indicating movement of the package, getting closer and closer to "delivered." By 10:30 tonight, it still showed "delivery by 8pm" but the package wasn't here.
I called customer service, and after checking they informed me that the package will be delivered on Wednesday. So, not only will I not have it before leaving on a trip  tomorrow evening, they planned to attempt to delivery it 2 days late, on a day when no one will be home, with a high risk of the package going missing. The best she could do is to contact the carrier and get it delayed until Thursday (when I'll be home) but, obviously that doesn't resolve the late delivery issue.

I guess I should have paid the $4 for overnight delivery. An option I still have, maybe: after talking to the rep on the phone, I checked and saw the item for sale on Amazon with a "deliver tomorrow" option, so I could place a new order, pay the $4, and hope it arrives before I have to leave for the airport. But that is too much of a risk.