Using history as our guide to future possible legislation, a new AWB would probably have a "grandfather clause". This means that since you own it already, you can keep it, but from now on (you children) you can't just go and do X, Y, Z. This is the way the last AWB was, since before the law took effect, SAWs were legal to make/own/sell SAWs.
So saying that a new but totally identical AWB was approved today, it would say you couldn't make a SAW from now on, but since they were perfectly legal the day before, your SAW would be "grandfathered" and remain legal. We would call it a pre-ban, since ya had it before the ban.
With that said however, there is no guarantee that a new AWB passed today would be identical to the old one. There could potentially be a gestapo style forced local registration of SAWs. There could be fees for ownership and liscensing and/or Kalifornia style no sell/buy restrictions. There could be a totally new definition to include "fast firing" rifles like lever action or pump guns.* So called "sniper rifles" (literaly guns with scopes) could even be re-defined as AWs*. THERE COULD BE --- NO --- grandfather clause at all meaning, "Turn that nasty gun in right now son..."
This of course is why its a good idea to stay on your reps donkey BEFORE these things show up on the radar, and why NOW is the time to buy IMHO.
One thing is for sure, there are NO guarantees if a new AWB gets passed.
Tex78
* - these things have already been proposed at both state and federal level before, and/or have been pushed by the gun control nazis before. NO KIDDING!