Thank you for your question. If there is an absolutely critical issue or security vulnerability we do have the ability to provide hotfixes on top of existing releases to clients. The emergency hotfix process is used only as last resort and any hotfix must be approved by GCS leadership. In the case where there was a more wide-spread issue, GCS would send an email campaign to all registered client contacts.
That being said we have fixed 99%+ of all issues through the patch release process and emphasize that is the most sustainable and quality way to deliver fixes.