Upgrading from 4.8 to 4.9 is not enabling the loadbalancer service on cloud-provider-config, so it is not possible to create loadbalancer services on the cluster.

In 4.8 it is needed to enable the loadbalancing service manually, following below procedure: https://docs.openshift.com/container-platform/4.8/post_installation_configuration/network-configuration.html#nw-osp-configure-octavia-load-balancing-services_post-install-network-configuration

However, since 4.9, above configuration is set by default. Furthermore, in 4.12 this configuration is even not visible.

It is observed that the upgrade from 4.8 is not enabling such a configuration. In case the expectation is that this config change should not be applied automatically, a note in documentation should  have been present so customers are informed accordingly.