Manufacturers do not recommend that you leave the products in the diluted states for more than 24 hours or you will risk the efficacy. The longer the products sit in the diluted state the more they will lose their potency. You can also risk breaking down the components on your hand pump sprayer. When stored in ideal conditions - out of extreme temperatures and direct sunlight - Eagle 20EW Specialty Fungicide will last for 5 years on the shelf. Shake the bottle well before use and yes, it will still be effective.
Eagle 20EW Specialty Fungicide should be used within 24 hours of mixing with water and applied and not stored. The undiluted product can be stored away from extreme temperatures (ina cool, dry place) for up to 3 years from the purchase date.