How can you be so confidently wrong? No, they won’t send a letter saying, “We’re coming over on XYZ day.” But they will send a letter asking you to come into the station. Once you're there, they'll ask if you have your phone if you say yes, they'll casually ask to see it, and before you know it, it’s in their hands. Then they'll politely ask if they can search your home. If you refuse, they'll just get a warrant and do it anyway.
I'm speaking from experience, you're probably speaking from chatgpt experience.