Andre Noel Denny was originally charged with second-degree murder in death of the 49-year-old man in April of 2012, but pleaded guilty to the lesser charge in November.
The sentencing began in Halifax Monday morning, but was postponed until Feb. 22.
Denny, a patient deemed not criminally responsible for his own actions in an earlier case, was issued a one-hour unescorted pass from the East Coast Forensic Hospital on April 6th, 2012, but didn't return.
While authorities were searching for Denny, Taavel was beaten to death outside a Halifax bar following an altercation.
The Nova Scotia government issued an apology to Taavel's family last month.
Health Minister Leo Glavine said a review identified significant gaps where improvements were required to ensure the protection of the general public.
Taavel's family issued a statement at the time saying they remain concerned whether patients deemed not criminally responsible can be found if they don't return to the hospital.