This issue was reported by David Bottger on bitbucket.org:

home-rsync can fail on pre-sync when files are deleted prior to syncing I can create a PR for this, given permission, but basically you just need to allow exit 24 from perform_rsync in prepare_backup_home

function prepare_backup_home {
  check_config_var "BITBUCKET_BACKUP_HOME"
  check_config_var "BITBUCKET_HOME"
  # this run is against live data, it is ok to fail due to vanished source files
  (perform_rsync) || EC=$? && if [ "$EC" != 24 ] && [ "$EC" != "" ]; then exit $EC; fi
}