Clem Lefebvre, head of the Linux Mint project, has announced that users on Linux Mint 19.3 (64-bit) can upgrade to version 20 without doing a clean installation. The option is helpful for those who don’t want to re-install and re-configure their systems but it also comes with more risk than doing a clean install.
According to the announcement, only users with a 64-bit Mint installation will be able to upgrade, this is because Linux Mint 20 is only available for 64-bit systems. If your computer is running a 32-bit version of Mint 19.x you can keep it till it expires in April 2023.
If you want to upgrade, the Linux Mint team has put together a handy upgrade tutorial which will guide you through preparing your system, the upgrade process, and the minimal clean-up required post-upgrade. If you’re intent on upgrading, be sure to read the appropriate release notes before cautiously following the upgrade instructions.
As mentioned earlier, Linux Mint 19.x releases are supported until April 2023 which is still a long way off so don’t be in a hurry to upgrade if everything works for you.