It was in Knitting magazine 80, which was published back in 2010, but handily you can buy the pattern and I think a kit as well from Purl Alpaca Designs.
I started this in February 2012. I knit the lower back panel, as seen here.
Then I stalled. You are supposed to knit the upper back by picking up a bunch of stitches along that top edge. I couldn't make the maths work so as to get the number of stitches just right on my first try, and I didn't want to mangle the knitting by picking up stitches in the wrong place too many times. So I just stalled. For over a year.
I picked up this project a few minutes ago and went across the top row just winging it, trying to pick up stitches evenly along the top edge and hoping for the best. I came in about 10% short of the desired goal. So on the return row I picked up extra stitches at even intervals until I got to the right total. Bingo. No problem. I just let that project sit in a bag for 16 months and that was all that needed doing.