It would be helpful to know when you have finished testing GeneratePress and its child themes against the latest update to WordPress core, so we know when it is safe to update our individual WP cores and not have to worry about GP compatibility with the latest WP update.
Perhaps you could push out a mass email to your email user list, or at least post such an alert on the GP website and GP Facebook page. Just something simple like “GP version x.x.x and child themes have been tested and are compatible with WP version x.x.x”.