Hi John,
For me personally it took 14 months from start to finish (my last exam). That includes a one month break between mod one and two.
I worked Monday to Friday 9-5 so studied in the evenings. I usually allowed myself 2 evenings off a week depending on how I was progressing.
I did the course with Bristol and found the progress graph on the software helpful in showing me if I needed to do some extra hours study.
I had a wife and 2 young children to juggle during my studies so depending on what your other commitments are then 9-12 months seems a realistic time frame.