rs on a VM when the VM sidecar is connected to <code>istiod</code> but a <code>WorkloadEntry</code> is registered later. (<a href=https://github.com/istio/istio/issues/28743>Issue #28743</a>)</p></li></ul><h3 id=upgrade-notice>Upgrade Notice</h3><p>When upgrading your Istio data plane from 1.7.x (where x &lt; 5) to 1.7.5 or newer, you may observe connectivity issues between your gateway and your sidecars or among your sidecars with 503 errors in the log. This happens when 1.7.5+ proxies send HTTP 1xx or 204