the `[sig-imageregistry][Feature:ImageStreamImport][Serial][Disruptive] ImageStream API` tests (all of them) modify the image.config.openshift.io. This ripples to the MCO and the openshfit-apiserver (at least). This causes every machine to restart at the same time that the openshift-apiserver rolls out. It then changes the configuration back. However, the test doesn't wait for a stable system coming back. this results in an unstable cluster for the tests that follow.
[Disruptive] keyword has been added, and removed from the test suite https://prow.ci.openshift.org/view/gs/origin-ci-test/logs/release-openshift-origin-installer-e2e-aws-serial-4.6/1304146128584839168
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 (OpenShift Container Platform 4.6 GA Images), 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/RHBA-2020:4196