Resolved
DNS records are propagating normally. This issue is resolved.
Issue
We have confirmed this is an issue with an upstream provider and will provide updates as we get them.
Investigating
We are tracking an issue with an upstream provider related to DNS record propagation taking longer than normal. The effect of this is any default domains for newly created apps in Private Spaces, custom domains added or updated to apps in the Common Runtime in the U.S., and or default domains for newly created apps in the Common Runtime in the E.U. may have DNS targets that take longer than normal to propagate across the Internet.