Got a mail from Cloudflare today
[...]
Fortunately, your domain is not one of the domains where we have discovered exposed data in any third party caches. The bug has been patched so it is no longer leaking data. However, we continue to work with these caches to review their records and help them purge any exposed data we find. If we discover any data leaked about your domains during this search, we will reach out to you directly and provide you full details of what we have found.
[...]
Still not very reassuring