On a Mac
be@HPH-iMac-02 ~ % juliaup --version
Juliaup 1.20.1
be@HPH-iMac-02 ~ % juliaup self update
Checking for new Julia versions
Checking for self-updates
Found new version 1.20.4 on channel release.
Juliaup configuration is locked by another process, waiting for it to unlock.
^C
be@HPH-iMac-02 ~ % juliaup self update
Checking for new Julia versions
Checking for self-updates
Juliaup unchanged on channel 'release' - 1.20.4
be@HPH-iMac-02 ~ %
The same thing was observed on my another Mac: Juliaup cannot find Julia - #6 by Eben60 - the juliaup self update apparently performed, but then the command stalled