I don’t think anyone would recommend going against the company that made the formula and tell you to switch to stage 2 formula that’s meant for 6 months and above. The stage 1 formula is easier for baby’s gut to break down and process. Starting stage 2 prematurely could potentially result in baby not being able to digest it well, and that could be dangerous. Perhaps consider persisting with stage 1 for just 2 more months before switching?