Manage Google Groups membership expiration with Google Apps Script and Cloud Identity API
As noted by Stéphane Giron Google Group member expiration is not available on all types of Google Workspace accounts, but this post is a useful reminder of what is now possible when it is. The most includes a full explanation and code to get started.
Source: Create membership expiration in Google Groups for Google Workspace
Member of Google Developers Experts Program for Google Workspace (Google Apps Script) and interested in supporting Google Workspace Devs.