When switching the baby squirrel from the Fox Valley 32/40 formula to the 20/50 formula, should we mix the formulas together and gradually increase the amount of the new formula? Like 1/4 the new formula on the first day, half on the second day, 3/4 on the third day and fully transitioned to the new formula on the fourth day? Or just switch to the new formula all at once when she's four weeks old? The estimate for her age is that she'll be 4 weeks old this Friday, August 25th. Also, if we should gradually increase the new formula's ratio, should we start adding the new formula a few days before the squirrel turns 4 weeks old, or start adding it right when she turns 4 weeks old?