I think your fine. The CO2 blanket on top of the beer will keep O2 from getting to it. Just make sure not to shake the bucket up too much.
First State Brewers
Primary: StrawberryHop Saison
Bottle: Rochfort 10 Clone, Bourbon Oak Pumpkin Ale
Keg: Kolsh, Marzen, Saison, Belgian Strong Ale, Brewskie the Elder,Pomegranate Apfelwien, Rye Dortmunder Export, English Bitter