Its not in my nature to wait for anything.. when I want something i want it when Im shopping.. I'd just move to the next brand.
Most brands are the same at the moment.
May last year I ordered a new Kia, and was told 6 months. As it got closer it then became Feb, then April then 2 more months, and today I was.told March next year.
I'd tell them to stick it, except if it eventually arrives if I don't want it, I can sell it and make 10-15k.