DB $20 off as good as it gets?

I'd probably at least talk to DB about the specific dress. My wedding isn't until September but my MOH just ordered because the dress she wanted has a lead time of 6 months! My other bridesmaid hasn't gone yet but they're allowed to get whatever dress they want within certain criteria, so she can pick something without such a long lead time if she needs to. But if you're required to have a specific dress I'd check the lead time! I know that doesn't answer your specific question (which I don't know a good answer for, sorry), but is definitely something to keep in mind!

They have a million sales all the time, so there might be something better.....but, yes, they do discontinue a lot.

Check your credit card terms of service and see if you have price protection. Usually if the price drops within a certain timeframe after you bought something, you can show the new price and the cc company will issue you the difference.

I got $100 off mine during a sale they were having several months back. I'd talk to them and see if they could do better or if there is a price adjust policy.

They have different sales all the time so you could wait. I would pay close attention to the ship date/arrive of your size because 6 people could be ordering the same dress and all get it at different times depending on your size.