Dagger,
I had read somewhere that there are people who were rejected after the tea party, applied again, got accepted and are currently training!
But based on my friend's recent experience, id be a bit conservative.
Only SIA would know the exact reasons as to why a second chance is not given.. from what i understand , its due to the repetitive nature of the tests and exercises of the second interview..
The best way, IMHO, is to re-apply and find out for yourself.
Joe