Independent? Is this a financial aid question? Having an IP PIN only verifies your identity. You can get one at any time, but then you will need to use it for every tax return from now on. However, an IP PIN doesn't prove you are independent, anyone can get one including parents can request them for dependents if there is a question of identity theft.
https://www.irs.gov/identity-theft-fraud-scams/get-an-identity-protection-pin