Our SSL certificate provider is going to be completing some maintenance. During this time it will not be possible to complete the setup of any new custom domains on GitBook.
The maintenance itself is expected to be completed between 14:00 and 16:00 UTC. However, due to DNS propagation time and possible delays in SSL certificate issuance before and after this smaller maintenance window, to avoid being impacted we recommend to set any new custom domains either before 12:00 UTC or after 17:00 UTC.
We do not expect this maintenance to affect any existing custom domains.