Issue
After updating to from Drupal 8.6 or earlier to Drupal 8.7+, entities can fail to syndicate consistently or have fields such as publish state modified. You may see errors like this in drupal-watchdog.log:
RuntimeException: Failed to start the session because headers have already been sent by "/mnt/www/html/<sitegroup>/vendor/symfony/http-foundation/Response.php"
The issue may also present in Acquia Lift, where content does not update properly or new content does not appear for personalization.
Resolution
Update the Content Hub module to version 8.x-1.39+. If you are using Content Hub 2, update to 8.x-2.5+. The updated modules are compatible with earlier versions of Drupal core and can be updated before updating Drupal to 8.7+.
You can check what version of the Content Hub module by loggyou are running using drush pml.
Cause
There were significant changes to how Drupal handles entities in Drupal 8.7.1. The Content Hub modules were affected by these changes and syndication became inconsistent. The modules have been updated to account for these changes.