Probation violations can be brought up to one year after the end of the probationary period. In addition, there may have been a term of good behavior imposed on your suspended sentence. If so then the statute runs one year after the expiration of the term of good behavior. If good behavior was ordered but no time period was specified, the default is the statutory maximum punishment - in a cocaine possession case, ten years. You can get a copy of the sentencing order from the Clerk's Office at the circuit court where you were tried which will give you the operative numbers in your case, or give a call to the attorney who represented you.
Pursuant to § 19.2-306 b of the Virginia Code, "The court may not conduct a hearing to revoke the suspension of sentence unless the court, within one year after the expiration of the period of probation or the period of suspension, issues process to notify the accused or to compel his appearance before the court. If neither a probation period nor a period of suspension was fixed by the court, then the court shall issue process within one year after the expiration of the maximum period for which the defendant might originally have been sentenced to be incarcerated. Such notice and service of process may be waived by the defendant, in which case the court may proceed to determine whether the defendant has violated the conditions of suspension." As such, if within one year of the period of probation, the court issues process to the Defendant or compels the defendant to appear, then the court may proceed with a hearing for a probation violation. If you are facing a revocation hearing for a probation violation, you should contact a qualified criminal defense attorney immediately.
This answer is for general informational purposes only. No attorney-client relationship is formed nor should any such relationship be implied. It is always recommended that you contact an attorney licensed in your state, that practices in the relevant area of law, to schedule an in-person consultation.