How to upgrade TeX Live 2026

Sorry, but I'm getting old.

For years, I upgraded my TeX Live system with the recipe at 
<https://www.tug.org/texlive/upgrade.html>, but now I'm stymied in step 8:

$ echo $PATH
/home/linuxbrew/.linuxbrew/opt/binutils/bin:/home/linuxbrew/.linuxbrew/bin:/home/linuxbrew/.linuxbrew/sbin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games:/snap/bin:/opt/texlive/2026/bin/x86_64-linux:/opt/texlive/2025/bin/x86_64-linux:/home/andreas/Work/tmp/lilypond/bin
$ pwd
/opt/texlive/2026
$ sh ./update-tlmgr-latest.sh -- --upgrade
Verifying archive integrity...  100%   MD5 checksums are OK. All good.
Uncompressing TeX Live Manager Updater  100%
./runme.sh: updating in /opt/texlive/2026...
./runme.sh: tlmgr version says this is TeX Live 2026,
./runme.sh: and this updater script created: Sun Mar  1 04:33:00 CET 2026.
./runme.sh: have TL 2026, new version also 2026;
./runme.sh: using --upgrade doesn't make sense; terminating.
(./runme.sh: makeself creation date = Sun Mar  1 04:33:00 CET 2026.)

Please advise!
Andreas