New (impossible and unfair) shipping requirements

Just got an email that packages have to be delivered within 6 business days which is just over a week. With usps delays and the fact I ship from one coast, this is basically impossible for about 30% of my orders. Are they going to shut down shops that can’t magically make usps work faster? Refund the money and then the person gets the product 3-4 days later for free? I will have to shut the shop if this happens.

Fulfilled by tik tok isn’t a great option since my product is meltable (chocolate) and they don’t do cool ship best I can tell.