I think i'll just download the ISO from here - https://getfedora.org/ but I know I can upgrade from the command line, so if you don't know how to do it, try this [please note i've not tried it so if it hoses your system, erm sorry], it also might cause issues if you have any third party repos enabled on your system, but give it a try any way.
Upgrade your software
sudo dnf upgrade --refreshInstall the dnf plugin
sudo dnf install dnf-plugin-system-upgradeStart the upgrade
sudo dnf system-upgrade download --releasever=31Start the upgrade and reboot
sudo dnf system-upgrade rebootGo and make a cuppa....
Enjoy Fedora 31