Having read quite a few of the threads and seen some of the excellent advice provided, I thought I'd register and tell you all my situation...in the hope of also getting some advice!
Myself (British) and my fiance (Australian) are based in the UK and have been together for 17 months. Although we are now engaged, we can not apply for a prospective marriage visa as we are getting married in Thailand in January 2009. So the de facto visa seems the way to go as we hope to move to Australia after the wedding.
We lived together independently between 15 September - 25 November 2007 (15 September was the earliest date we could move in together due to separate contractual rental agreements), then we visited my future in-laws in Adelaide (with me on a working visa) where we lived together, but also with them in their family home until end of February 2008. We then came back to the UK and have been living together since 5 March 2008.
Does anyone know whether our living situation above would count as 12 months together, if I applied on 15 September 2008? That is the only eligibility requirement I'm stressing about!
There are probably more questions I want to ask, but there are so many things buzzing around my brain, I can't think of any just now!