See https://issues.redhat.com/browse/ART-2818 and https://github.com/openshift/os/issues/542 and https://github.com/openshift/release/pull/18642 ART is running a new service.
Propose PR was merged into 4.8.0-0.nightly-2021-06-09-214128, we're using the new rhcos-redirector.apps.art.xq1c.p1.openshiftapps.com URL in baseURI now. No other issue found, move the issue as VERIFIED.
Since the problem described in this bug report should be resolved in a recent advisory, it has been closed with a resolution of ERRATA. For information on the advisory (Moderate: OpenShift Container Platform 4.8.2 bug fix and security update), and where to find the updated files, follow the link below. If the solution does not work for you, open a new bug report. https://access.redhat.com/errata/RHSA-2021:2438