Based on the regions and shipping status, there is no correlation with regions, so the only other is shipping method. Unless egrims is messing around, the people that ordered "next day business" have not been shipped, but some with two day, or free 3-5 day have.

Next day is usually pretty quick on the draw for updates, due to the movment process for expedited product and to reduce service calls from customers. This is the nature of "business" shipping, so there should not be any lag compared to the other shipping options. If anything, the slower methods would have lag of up to 12 hours. By the nature of "next day", there would be virtually no lag for updates.

If no updates by noon- this theory is correct. Looks like the shipping method may also be linked to where the product is shipping from and who received allocations. Only logical conclusion- if no updates by noon.