I have a Pixel, Android 8.1.0. I prefer to receive tweets via SMS. I will read and delete the entire conversation a message at a time after I have read them. Later (it could be hours, or a couple of days) the ones I have read, plus others I have not previously seen reappear from several days back. They are time stamped from when they originally came in. Sometimes I get as many as six days worth. This does not happen with any other conversation stream other than Twitter. I have asked Google and they say to ask Twitter. I have asked Twitter and just get the run around with the support bot.
