I ordered my RTiC 65 about a month ago. At the time it said "back ordered will ship August 23rd"
I just got it on the door stop last week. So, two weeks sooner than it was supposed to be. Haven't thrown anything in it yet, but it's pretty dang sweet. Can't wait to use it.
I had ordered a 30oZ tumbler a while back also, it was in stock and arrived a few days after I ordered it.
Long story short, I don't think you have anything to worry about.