A:AnswerYes the ssd and the hdd are up-gradable, there is a warranty sticker over one of the screws but it does not void the warranty in the US. The HDD is the easiest to upgrade though, the M.2 slot requires a lot of disassembly.
A:AnswerI wouldn't expect a sale any time soon. I might even question if you saw the correct laptop since there are cheaper ones with lower end graphics cards. I bought it around the time you asked this and I had been watching it for months. It had never gone on sale other than $100 off at one point. But not as low as $1499. I think you were looking at a different model.