When downgraded from premium, prior environment-specific variables are not passed anymore

Summary

If an account is downgraded from premium to free, it seems that CI variables which were previously passed to specific environments (premium feature, apparently) will no longer pass to any environments. Problem is solved by deleting the old variable and recreating it from scratch.

Steps to reproduce

1. Start a project on premium with CI, include CI_DEBUG_TRACE: "true" in .gitlab-ci.yml.
2. Pass variable to the specific environment defined by that branch
3. Run pipeline and observe that environment is correctly includeed in export
4. Downgrade to free version, run pipeline and observe that environment is not included in export (as though it wasn't passed through by gitlab at all)
5. Delete then recreate the exact same variable from scratch, rerun pipeline and observe that variable is passed.