Here is my answer from the comments:
The short answer is, that is a conservative response. There are things outside our control, like delays for the dockworkers, that we cannot control. We tried to create a conservative response. I'd hate to promise October, you plan on it for Xmas, then we miss that.
We hope to send the files to our manufacturer before the campaign ends so we can get started. Right now, we have to finish rules layout (85% there), we have 1 more spell to balance (we'll write about that later this week), and we have to create back of the box layout.
Once we send the files, here is the approximate time line:
4-8 Weeks for Pre-Production
6-8 weeks for Mass Production
3-4 Weeks for shipping
So, assuming worst case for all of those, if we get started at the end of our campaign, that puts us at December. We then need to ship all the copies, which will be our #1 priority but adds a little more time.
Things that might cause delays:
If a huge publisher has a big order, our project might get delayed at manufacturing. We're a small fish!
Last year, there were tons of strikes on the west coast of America, leading to huge delays we cannot stop.
As you can see from the time line, there is a chance you'll receive your copies sooner. We've worked hard to remove all delays in our control. But, we aren't confident promising that.