My experience with car dealers is your appointment time does not matter and should be viewed as a suggestion only. It is unfortunate but they also have limited resources. You can't realistically predict how long a car is going to take to fix before you know what the problem is. So, this 0ften times results in delays. I would suggest getting there at days and times where you can better predict that a resource will be available... at the time they open, for example.
I wouldn't put up with it, but sometimes they run into delays. Sorry to hear your going through this.
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