As soon as you get the withdraw effects take it (at least 24 hrs)
How Long After Last Dose Of Opieots Can I Start Suboxone?
Doctors recommend you be free of opiates for 24 hours before starting Suboxone. You must be in full withdrawal or the Suboxone will put you in withdrawal.
I only waited 12 hours. Before taking subs , I had mild withdrawal symptoms at the time.