Hi. Thank you for your question and reaching out. I’d be more than happy to help you with your query.
Every month, the installation package is updated. Before using, be sure you obtain the most recent package. You don't need to launch the installer package once more in order to update after installation. If you want to do so, the installer will ask you to log off first because doing so is necessary for removal. Please see Update packages for Microsoft Defender for Endpoint on Windows Server 2012 R2 and 2016 here https://learn.microsoft.com/en-us/microsoft-365/security/defender-endpoint/configure-server-endpoints?view=o365-worldwide#update-packages-for-microsoft-defender-for-endpoint-on-windows-server-2012-r2-and-2016
If the reply was helpful, please don’t forget to upvote or accept as answer, thank you.