gitlab.com is implied since it happening on a self-hosted instance would have nothing to do with gitlab as a service (they can't be responsible for your on-site backups).
> Trying to restore the replication process, an engineer proceeds to wipe the PostgreSQL database directory, errantly thinking they were doing so on the secondary. Unfortunately this process was executed on the primary instead. The engineer terminated the process a second or two after noticing their mistake, but at this point around 300 GB of data had already been removed.
https://about.gitlab.com/blog/2017/02/10/postmortem-of-datab...
