Yes they can extend the schedule, but the FTC has clear cut rules for business operating in the US about how they must go about that.
They can't just not ship the miner. If there is a delay it has to be reported to all of the customers. And at that point the customer is able to chose to agree to the delay or decline the delay and ask for full refund.
Thier rules don't supersede federal or state governmental rules or mandates on proper business practices.
That said I was told by AMT I had package being delivered, they've not got me the tracking number yet so I went ahead and called FedEx customer service. They confirmed I had a package in route, and that it is scheduled to be here on thursday the 10th. I'm hoping it will arrive wednesday. I would suggest anyone who was told their miner or kit has been shipped to call fed ex. Just know they won't release that tracking number to you. You'll need to get that from AMT.
AMT feel free to post my tracking # here I've already posted my address in the thread so it's no secret.
For your own sake that is not a smart thing to do. And I would tell them to email it to you directly. Then you can post it if you wish since it would be your liability at that poin. Since your address and now tracking number are public knowledge on here anyone within the right distance can swipe your miners. You MIGHT be around to receive them, but then again the person with malicious intent can also swipe them at gunpoint (and just because you might have one does not mean they cant get the drop on you). It happens more than you might think. Just some safety advice. Not a smart thing to do.