It could have been me you're thinking of - I posted a timeline in the Barclays AAdvantage Aviator... thread a while back with my timeline HERE.

I always thought you had to wait two years after closing a card before applying again, but that just doesn't seem to be the case. In my example above, I got a Red, PC'd it to a Silver, and then to a No AF "White" Aviator card and got a new Red, all within 2 years - and while still holding the previous card (previous card number anyway - the color of the card had changed but it was the same account). I still hold both the No-AF White, as well as the new Red. I got the full 70k SUB on the new Red.

At the time I most recently got the Red (August), the SUB was 60k for the normal $99 AF + one purchase. Then they offered an additional 10k if you added an AU and they made one purchase.

Edit: It's my experience that Barclays limits the SUB to two years between card approvals - not two years after closing a card. But even so, you can see (and I've read other DPs saying) that even that two years between approvals is somewhat flexible.