VPN client IP Priority

Where in the Sophos Firewall configuration do I set the priority of the external IP addresses for a VPN client to connect to? Issues is a Firewall which I have read only access to has a the IP address for Interface Port4 (cellular/LTE) listed before the IP for Interface Port2 (CableModem) on the .ovpn profile files. This causes VPN clients to connect over cellular and its slow unless I download, edit and reimport the ovpn profile for each user, manually prioritizing the Cable IP over the cellular. Appreciate your assistance!