This video goes over the Victron Inverter Switch and specifically the "APP Only" control and how to transition between the two.
The app is added to the van in the event there is a failure with the switch. This allows the inverter to be controlled by the VictronConnect app, so you are not down and can continue to use the van until a convenient time to repair the switch.
A screwdriver and set of pliers will be needed to convert this if you don't currently have the plate installed. Access to the panel is achieved by the back of the van. The panel is up by the breaker boxes. For ease of access, it is recommended to swivel the HairVac out of the way before starting.
First, remove the ethernet cable that is currently installed in the plate. Then using the screwdriver, remove the two screws holding the plate onto the box. Using the pliers, pinch the two sides and gently pull away from the plate to remove the switch connector.
With the new plate, reinstall the connector. Note which way the app control port is oriented and mimic it with the switch port. Now carefully put the plate back on the box, making sure to not kink or pinch any wires as this may cause the switch to not work. Reinstall the two screws to secure the panel to the box.
In the event you need to use the app port, remove the ethernet cable from the switch port. Insert it into the app port. Using a phone, get on the VictronConnect app. Find the inverter and connect to it. Select the mode button and go from "ON" to "CHARGER ONLY" and hit ok. Once the switch is repaired, reverse this process to go back to switch mode.