The manufacturer needs time to make the dress, ship it and get it to the company. Most dresses take 16 to 20 weeks PLUS shipping time and then you need time for alterations. Sad fact of life, all dresses need some form of alterations.
A custom ordered dress is different from a custom dress. Custom ordered is ordered especially for you according to the company's size chart. A custom made dress is made to your exact measurements and will cost a lot more money. Regardless, it will still need some tweaking to fit properly. No dress EVER EVER EVER will fit you exactly without some form of alteration, and if you are the one in a kabillion exception, congratulations, you've beaten the odds.
The odds of the company having the dress you want in stock in your size and color are roughly the same as hitting Powerball. There is no getting around the time frame unless you want to pay a rush fee and that will only knock off a a couple of months. The company charges you a rush fee to cut it especially for you. Rush is approximately an 8 week time frame, then you need to add shipping time and alterations. You will not only have to pay the company's rush fee, but the rush shipping costs to get the dress to you.
The time of year also affects whether the company can do a rush cut. During Chinese New Year, the companies DO NOT do any rush cuts. Most wedding gowns are made in China. Its a fact of the bridal business whether anyone likes it or not. The intricate hand beading is done in China, you can't get it done in the USA unless you are willing to pay a small fortune.
Not all companies do rush shipping and companies that do rush may not do rush on every dress. The companies also have the right to stop doing rush cuts during their busy times. Avoid disappointment, if the dress is "THE ONE", just order it and don't wait because you think you still have time.
This past week I had a customer who didn't want a dress made in China. She insisted that she knew that certain lines were NOT made in China. They are. She refused to believe me. Read the tags, lady! Because the line is based in Spain or Australia, the gowns still are manufactured in China. Eden dresses are made in Vietnam. Fact of life, there are few lines made in the USA. Vera Wang's is the only one that comes immediately to mind.
If you've had the "hallelujah moment" where the skies open and the angels announce that this is THE dress, then order it. Don't hesitate and keep shopping. Just do it. You'll save money, time and your sanity if you procrastinate.