Re: upgrade to testing

[Gary Dale]

On 2021-06-15 13:26, Wil wrote:
How do I upgrade from Debian stable to Debain testing?

It's not really an upgrade. It's more a switch in priorities. However to 
answer your question directly, as root do either

    sed -i -s 's/buster/bullseye/g' /etc/apt/sources.list

or

    sed -i -s 's/stable/testing/g' /etc/apt/sources.list

depending on how your source.list file refers to the current stable 
distribution.

After that, do

    apt update
    apt full-upgrade
    apt autoremove

then reboot.