Can TCA evidence be temporary

I raised this question as part of another thread, but it went unnoticed and I really would like some opinions on it.

On the recommendation of a friend (who is something of an Italian wine buff), I picked up a bottle of Rosenblum Zin - Richard Sauret Vineyard - 2003 (US$12.49 at Costco..... my friend paid $18 at BevMo - h-m-m-m) and we tried it with some pizza. The 2002 vintage of this wine was a 92 point WS pick, I think. The immediate sensation was very musty. I didn't really taste anything off, though the wine seemed very flat at first, but the mustiness was very strong. I've had this same thing happen a few times with an Antinori Chianti I used to like. After about 20 minutes the mustiness had gone and the fruit was very much present. This became a really good Zin I would go back for more of, but the initial mustiness was pretty daunting.

Now........ is that TCA?? or not? Does TCA 'air out' of a wine once it's opened, or is it simply there or not there?

I also have an interesting side note to this. I spoke with the friend who recommended the wine, to ask if he has noted anything similar. He had not noticed the mustiness, but the couple bottles he has had both exhibited the same need to stand for 20 or 30 minutes for the fruit to come out. IN ADDITION, his opened bottles both had synthetic corks in them, while mine is definitely a natural cork (Same exact vintage). I'm wondering whether this has anything to do with how Costco got this wine and whether the 'corkiness - mustiness' was part of the unusually large price difference.