Clarifications for dual-stack

Signed-off-by: Bridget Kromhout <[email protected]>

Author: bridgetkromhout

keps/sig-network/563-dual-stack/README.md

@@ -1379,9 +1379,9 @@ This capability will move to beta when the following criteria have been met.
 
 This capability will move to stable when the following criteria have been met.
 
-* Support of at least one CNI plugin to provide multi-IP
+* Support of at least one CNI plugin to provide multi-IP ([Cilium](https://cilium.io/blog/2021/05/20/cilium-110) and [Calico](https://www.tigera.io/blog/dual-stack-operation-with-calico-on-kubernetes/))
 * e2e test successfully running on two platforms (Azure and kind)
-* testing ingress controller infrastructure with updated dual-stack services
+* dual-stack service object is backwards-compatible with existing ingress controllers, so ingress controller infrastructure remains the same with updated dual-stack services
 * dual-stack tests always run as pre-submit (non-blocking) for PRs