First of all hello everybody, this is my first post here

I've just receive an email from cisco that said: Your CCNA Cisco Certification will expire on 10/20/2012.
I have one question. i think that i could take any ccna concentrations exam (voice/wireless/security) and then my CCNA will be "activate" again for three years more, am i wrong?
Another question, I'm not very sure if i may take the exam after 20th of October or if i must take it before this day so that I won't lose the CCNA 640-802 certification.
Thanks!!