I saw a few posts from Reddit users regarding shipment notifications... I think as always you have to parse the statement fully. "Ships by May 5th" means it ships on May 5th or before May 5th, but they re not guaranteeing it will ship before May 5th (It's synonymous with, ships no later than May 5th). Neither are they guaranteeing it will arrive by X date. Id take it this stance is another lesson learned from past experiences, don't make promises you cannot keep. Bottom line is, it's out of their hands once it ships.
I know there were people jumping thru all sorts of hoops because they were going to be here one day there the next and elsewhere the day after that. If you have special needs, work it with the shipper. Or buy in person and avoid shipping.
I should add, I'm pretty sure they have orders to NOT deliver B4 some date presumably May 5th or maybe is the 6th IDK. Some localities obviously take more time to reach from the nearest shippers office so they may start earlier or finish later possibly more than a day.