I wouldn't expect much to change unless this test goes on for at least a year. I say that because what I do know this: I've used Stabil for years in my snowblower, adding it to the remaining gas in the blower's tank in mid to late March. I then run the engine for about ten minutes to make sure the stabilizer is spread throughout the entire fuel system. The machine is then stored in a wooden shed which is in a shaded area of my yard.I'm in watching every month.
And has subsequently started right up when i take it out of storage 7-8 months later in the late October early November timeframe. I've also had similar experience with using Stabil in my lawnmower.