Nobody is asking how many they will get. People want to know when they are likely to get their camera. By answering a customer's question on when they are likely to ship the camera is not going to reveal their numbers nor will it reveal any 'special' agreement with Canon. And by the way I doubt that would be the case. This is USA, if that got out and if Adorama/Amazon did not sue to Canon some other two bit retailer could. Why would Canon risk it?
The reply from B&H when asked, "When will my camera ship?" has been "We don't know how many we are getting, we don't know when yours will ship." And you think B&H doesn't have a deal with Canon? Why does Canon allow them to be an authorized retailer when they also offer grey market Canon gear? And in order for someone to sue Canon for allotting more bodies to B&H there would have to be a law against doing that? Do you think the US Government attempts to regulate how Canon chooses to allocate inventory? Of course they don't.
But they know how many they ordered. I have heard the same thing from a number of retail shops, including small local shops, they ordered x but not sure what they will get. Now I buy that argument, may be Canon cannot tell them for some reason how many they will get on a given shipment. So even though they know what they ordered they cannot be sure how many they will get, and furthermore how many they will get the subsequent shipments. This would be a natural outcome where if the camera is really popular as it appears to be, Canon would be sharing the current inventory between a number of retailers so they may end up shipping fewer than what the retailer asked for. Hence the uncertainty on when a customer may get their order shipped.
You did not say 'deal' you said 'special deal'. I doubt Canon gives BH special treatment. It would be against fair business practice and would look really bad on Canon if it came out you can bet someone will think of suing Canon (not that it would be easy to prove, but that will not stop people, it is our national sport). Just because Canon is allowing BH to sell grey market Canon products, does not mean BH will get preferential treatment when it comes to fulfilling their stock request, in fact the opposite may be true, who knows? BH is a big player and I suspect their allotment is one of the largest, but that is it.