Ha, that was funny.  But I recall SineBot (or its predecessor) used to wait a while before butting in.  Perhaps that wasn't intentional behaviour, but I recall having a few minutes to finish and sign, and having done so a few times.  If you can make it do so, that would be good.  P.S.: Yeah, I could leave this on your user page, but really, why not just direct people to leave feedback here? You are monitoring it after all.  No reply needed; just some feedback.