Why is portupgrade not logging?

[mal content]

I am running the command like this:

DATE_YEAR=`date +%Y`
DATE_MONTH=`date +%m`
DATE_DAY=`date +%d`
LOG_BASE="$HOME/var/log/portupgrade"
LOG="${LOG_BASE}/${DATE_YEAR}/${DATE_MONTH}/${DATE_DAY}_%s:%s.log"

portupgrade \
  -aRrv \
  --batch \
  -L "${LOG}"

No files are ever created in ~/var/log/portupgrade/2007/05.

Am I misunderstanding something about the -L switch?

MC