Mine finished at around 1.008 and I do not recommend letting it go that low. Mine isn't bottled yet but my sample tasted terrible. It was extremely tart and tasteless. I would try to stop it earlier if you could thought you could back sweeten which is what I plan on doing.
Primary: Sour Brown
Secondary: West Flanders Red, Golden Sour, Saison Brett #2 with Brett custersianus and Brett naardenensis, Saison Brett #1 with Brett bruxellensis
On Deck: 100% Brett IPA, West Flanders Red #2 with ECY BugFarm