Hello Raven-
You cease to belong to a religion on any day you chose to be gone. No need to inform anyone, give any reason or answer any questions - period.
Religion and belief are voluntary situations of individuals not required or controlled by law. Freedom of Religion is a legal right of every person and gives the individual the right to abandon any belief at any time for any reason.
Anyone who exerts their now unwelcome 'ecclesiastic authority' after you have chosen to be free of it, is violating your right to be free of that religion as the Norman Hancock case showed.
Prove you have truly abandoned the religion by emailing a trusted (non-JW) friend with the news and keep that email as a legally dated proof of your freewill action of having already abandoned a belief or organization you no longer support.
NEVER RETURN, or share, or allow yourself to be counselled or interrogated as you did when you previously accepted the ecclesiastic authority of the groups elders. The longer you remain away the stronger is your claim of Freedom of Religion.
Your right under law to be free of a religion is exactly as valid as is the right of that religion to exist. Freedom works both ways - that's why Jws never discuss human rights such as freedom of religion.