The basic recipe for upgrading using CPAN is:
sudo -H perl -MCPAN -e 'install SVK'
Or if you have a sufficiently up-to-date copy of the CPAN module (which installs the
cpan command-line tool):
sudo -H cpan SVK
The first time I tried to update I got an "already up-to-date" message. It seems I need to look for better mirrors. I did a
sudo -H cpan and entered
o conf init so as to pick some different mirrors, and then finally
install SVK worked.