If you are in the bridal industry, you know bridesmaids take about 3 months to order. You are always given an estimated ship date and if it's too close for your comfort, you add a rush. PERIOD.
It amazes me girls complain and stress when bridesmaid dresses come in a month or even 2 weeks before their wedding date.
First, don't wait until the last minute and if you do...expect to pay a rush charge. If you don't, deal with the consequences.
Second, it doesn't take a seamstress more than an hour or two to alter your average bridesmaid dress. 2 weeks is MORE than enough time to do alterations.
Three, if you order a different style or diferent styles, they will not all ship at the same time. They will come from different cuts of fabric, unless you order all the same style and push the order all at the same time.