Recently, Google has quietly introduced a way to de-register your phone number from RCS messaging. Google currently all Android messaging over RCS which lets users send messages over the internet rather than the short message service (SMS). RCS allows for read receipts, full-res image sharing, and typing notifications for both individual and group chat threads. Google's new page offers instruction on how to turn off the "Chat features", which effectively turns off RCS chat. The page suggests that you can turn chat features off if you are missing messages before switching to a new Android...
Source: https://www.gsmarena.com/google_makes_it_possible_to_deregister_your_number_from_rcs-news-43868.php
