When does IBSS and IBEC come into play?

[jamesapp]

I really don't care about unlocking. I didn't get the iBEC IBSS file numbers. I have a 3gs, can't I just wait for the 3.1 jb and then update my iPhone to 3.1 and then jb it? Then I would have a jailbroken 3gs running 3.1? So I wouldn't be able to restore it? I guess if I am running 3.1 I can't restore to 3.0 because I didn't capture those files? So if I tried to restore I would just get an error message saying my iPhone couldn't be restored? If you are running a jb 3.1 firmware would there be a way to restore to unjailbroken 3.1 firmware? I know some of this is hypothetical, but some clarification would be nice.