When a person has been sentenced as a sexually violent dangerous offender under ORS 137.765, the maximum period of local custody to which the State Board of Parole and Post-Prison Supervision or the local supervisory authority may sanction the offender for any violation of post-prison supervision is 180 days. Notwithstanding ORS 161.605, the sanction may be imposed repeatedly during the term of the post-prison supervision for subsequent post-prison supervision violations. However, the board or local supervisory authority may impose only a single sanction for all violations known to the board or local supervisory authority as of the date that the sanction is imposed. [1999 c.163 §2]