So all I can tell you is that mine's an S3, so different engine, and the only options you've got that I haven't are: diamond cut wheels, lumbar support and wireless charging. I was given Build Week 17, it was then brought forward to 14 (this week) and has now been built. So it could be the engine or one of your options in short supply or, like I say, some sort of dealer/factory politics. Who can say? I think you're entitled to ask why your build week has been pushed back though as it's a valid question. Just being told 'it wasn't final' or 'it was subject to change' isn't really an answer.