It is strongly recommended to create a backup before starting the update process. If you have important data, create and restore a backup to ensure that everything works properly.
You can upgrade the application itself without modifying any other component included in the stack by executing the following commands as bitnami user or the user who installed the application:
$ cd /opt/bitnami/apps/erpnext/htdocs/frappe-bench $ . ../venv/bin/activate $ bench update --reset $ deactivate