I have been preparing bottles of formula in advance (using powder, and cooled boiled water) and then storing them in the fridge and using them within 24 hours. I have just read in one of my books that, in fact, formula should not be made up in advance .... is this true? I asked my GP and he seemed to suggest that the author of the book was being over-cautious and that it is fine to prepare formula in advance... what do you think?