In 2018 and 2019, Kirsty Harmon from Blenheim Vineyards explored dosage levels and timing of SO2 addition post-malolactic fermentation in Cabernet Franc and Cabernet Sauvignon. Her studies found that larger initial dose of SO2 post-malolactic fermentation led to better aromatic complexity and less spoilage than smaller, more frequent doses. Large additions were more likely to allow wine to age at the target molecular SO2. Also, delaying the initial dose by 2 weeks led to lower total SO2 overall.
In June of 2020, Virginia Winemakers gathered virtually to discuss SO2 management and to taste results from an experiment performed by Kirsty Harmon of Blenheim Vineyards. Here is the link to that recording.