The 2020 model isn't even a year old and it's already on sale. The timing suggests that Lenovo may announce a revision with 4th gen Ryzen options this Summer to replace the last year's 3rd gen options.
https://www.notebookcheck.net/Lenovo-Flex-5-14-2-in-1-with-Ryzen-7-4700U-16-GB-RAM-and-512-GB-NVMe-SSD-is-at-its-lowest-ever-for-599-USD.530482.0.html