upgrading from 2020 to 2021

[AC]

I am trying to follow the instructions at 

https://tug.org/texlive/upgrade.html

verbatim.

With my path pointing to the 2021 folder, and the latest update-tlmgr-latest.sh, running

sh update-tlmgr-latest.sh -- --upgrade

returns

Verifying archive integrity... All good.             Uncompressing TeX Live Manager Updater  100%         ./runme.sh: updating in /root/texlive/2021...        ./runme.sh: tlmgr version says this is TeX Live 2020,./runme.sh: and this updater script created: Fri Feb 12 02:40:05 CET 2021.                                ./runme.sh: have TL 2020, new version also 2020;
./runme.sh: using --upgrade doesn't make sense; terminating.
(./runme.sh: makeself creation date = Fri Feb 12 02:40:05 CET 2021.)