Comment 3 for bug 2022102

An older cloud-init deserializing a pickled Datasource cached /var/lib/cloud/instance/obj.pkl from a newer verion of cloud-init is an unsupported use case.

That said, there is work in progress that will allow to sourcing /run/cloud-init/merged-cloud-config which will allow subiquity to consume user-data without reading from a cached pickle of instance data.

https://github.com/canonical/cloud-init/compare/main...blackboxsw:cloud-init:SC-1452-persist-run-combined-cloud-config-json. An update will be provided here when that feature has landed.