Which TIA Portal versions are supported?

We have projects in V17 and V19. Does it work with both? Can it convert a project between versions?

PLC Sidecar is built for TIA Portal V17 to V21. Most of our production use so far has been on V17 and V19.

Each project is opened in its own TIA version and changes go back in the same version. The app does not migrate projects between versions (e.g. V17 → V19); that stays a job for TIA Portal.