I bought my iPhone 5s about a month after they came out. The delivery took a month. But as soon as it was listed as dispatched, it went from a location in China to England in about 3 or 4 days. So it's pretty quick. That's with a few stops as well in between. It stayed for a night in Germany near the end of the journey over to the UK for some reason. So it is quick.
Edit
With this being an iPad, obviously there is a lot less of a demand. They'll be stored at warehouses up and down the country depending on where you live so there really is no way to tell. The warehouse might be close to you but far away from where I am. I'd expect it by probably Friday, maybe Saturday at a push.
