Hunting for a nemesis bird

Well, there's the habitat. Brushy lowland that is perfect habitat for the bird I'm looking for.
What nemesis bird do you think it could be? No, it's not a WI bird. I've already seen every WI bird that frequents this habitat.
Not a WI bird you say? yep, it's rare here. It's a southern bird, a bird that's normally found in the southeast. Any guesses yet?
No, it's not a duck, nor a goose.... No, it's not a rail, not even a warbler. Got it? Here's another hint, it's a passerine. More? alright, it's not a sparrow either. Still not have it? Here's the last hint: it's a bird that I've been after for a long time. A bird that I've missed countless times. A bird that I've missed only by hours and sometimes minutes. If you know me, then you know now which species it is. You're probably on the edge of your chair right now waiting to hear if I found it. ;)
You can stop the suspense, I haven't seen it yet. This time I dipped by about 24 hours.

Instead, this BC Chickadee posed very nicely for me:

I'm trying again at 5:30 tomorrow morning. Hopefully the bird will be there. I soo want that bird!!