MDAccess for Polarion supports the same versions of Polarion ALM as those officially supported by Siemens. Refer to the Siemens Polarion website for the current list of supported versions.
No breaking change in the Polarion web service API has been observed since Polarion 19. As a result, MDAccess for Polarion is expected to work correctly with versions of Polarion ALM going back to 19, even if those older versions are no longer officially supported by Siemens.
Note: Document baselines (i.e. baselines scoped to a specific LiveDoc rather than an entire project) were introduced in Polarion 19.2. Querying document baselines with QueryBaselines therefore requires Polarion 19.2 or later.