Hi, just want to get peoples views on the preparation of this milk. The instructions tell you to leave 500ml of boiled water for 45 minutes and then prepare bottle. Is this really safe for our 4 month old though as do they not want you to make formulas with water at least 70 degrees not cooled for more than 30 minutes. Do you go with what the manufacturer states as it's a formula meant for a specific purpose or with NHS information? We made one bottle with freshly boiled water and it didn't go lumpy, however on the edges of the bottle there was little bits that wouldn't dissolve with shaking?