Currently the cutoff for the first 10,000 is between order 465 and 475. The cutoff for the first 20,000 is between order 515 and 540.
Terrahash Order Tracking
100% pure speculation of course. Since NO ONE has any damn clue as to what or how they are handling orders. It's freaking circus for now.
I wouldn't call it 100% pure speculation. This list assumes that they will fullfill orders by order number and is based completely on order data. They have come out and said they plan to cut out orders off the que that we're not paid for yesterday with the exception of bank transfers. But even that isn't completely clear as to how it will work.
I also would much rather trust the order data here than the whatever arbitrary date they could throw in an e-mail. The trust level at the moment isn't extremely high. This data should act as a method of confirming their e-mails unless they wish to make their order data public so dates can be validated by a 3rd party.