well first, i'm gonna reiterate what i said in the following post. don't worry. really. if you're calling exactly 180 days out from the ADR, you're almost guaranteed to be fine. if you're 180+10, it's a little trickier but nothing to get disheartened over.
i don't think it's mentioned in that thread, but it's been mentioned elsewhere so.. the real trick is that the lines really open at 6:58 am. go by time.gov for the current time is, not what your clocks say.