On Mac desktop/laptop computers it is build 4.23.3 which was released November 17, 2023. To upgrade to the latest version either wait for the automatic update or go to https://preveil.com/download, download the installer and run.
The automatic update is part of a staged rollout plan where app updates gradually increase following the release date.
Update Nov. 22, 2023, the Windows build has been rolled back to 4.23.2 owing to reports of stopped IMAP and SMTP services.