Statute of Limitations for BON to Act

I am a nurse on WHPS after quitting a job abruptly, the DNS & Admin reported me to the BON for suspected drug use. My quitting followed reporting the facility to the State for multiple patient care violations (they found out about the anonymous call) & giving patients the 800 # for the nursing home abuse hotline (which I was verbally reprimanded for).

I have never used drugs or even drink alcohol, and had taken several drug tests for this employer during my year of employment with them.

The BON found no wrong doing other than 2 documentation errors (assessment follow ups) after administering 2 alert middle aged patients narcotics per their request.

I have no fight left in me and signed the BON documents & was placed in WHPS. Are there any statute of limitations with these things, my last job was almost 5 years ago & the BON just finished their investigation & placed me in WHPS last Summer.