Comment 3 for bug 1830745

In both stateful and stateless deployments, the relation data is is lost, so there does not appear to be a workaround (beyond rewriting charms and interfaces and redesigning the relation protocols to support the different k8s and traditional charm lifecycles).

The Juju 2.7 updates will certainly help, but making use of the feature will require rewriting charms and interfaces and redesigning relation protocols and updating existing production deployments (which isn't as bad as it sounds, given this already needs to happen to support cross model relations, which is required to relate k8s charms to traditional charms).