diff --git a/cmd/prometheus/main.go b/cmd/prometheus/main.go
index eaa97fe32..9b662249b 100644
--- a/cmd/prometheus/main.go
+++ b/cmd/prometheus/main.go
@@ -168,10 +168,10 @@ func (c *flagConfig) setFeatureListOptions(logger log.Logger) error {
 			switch o {
 			case "promql-at-modifier":
 				c.enablePromQLAtModifier = true
-				level.Info(logger).Log("msg", "Experimental promql-at-modifier enabled")
+				level.Info(logger).Log("msg", "promql-at-modifier enabled")
 			case "promql-negative-offset":
 				c.enablePromQLNegativeOffset = true
-				level.Info(logger).Log("msg", "Experimental promql-negative-offset enabled")
+				level.Info(logger).Log("msg", "promql-negative-offset enabled")
 			case "remote-write-receiver":
 				c.web.EnableRemoteWriteReceiver = true
 				level.Warn(logger).Log("msg", "Remote write receiver enabled via feature flag remote-write-receiver. This is DEPRECATED. Use --web.enable-remote-write-receiver.")
diff --git a/docs/feature_flags.md b/docs/feature_flags.md
index fd09c4088..33d822135 100644
--- a/docs/feature_flags.md
+++ b/docs/feature_flags.md
@@ -18,6 +18,11 @@ They may be enabled by default in future versions.
 The `@` modifier lets you specify the evaluation time for instant vector selectors,
 range vector selectors, and subqueries. More details can be found [here](querying/basics.md#modifier).
 
+This feature is considered stable, but since it breaks the invariant that
+PromQL does not look ahead of the evaluation time, it still needs to be enabled
+via this feature flag. The feature will be permanently enabled (and the feature
+flag ignored) upon major release v3.
+
 ## Expand environment variables in external labels
 
 `--enable-feature=expand-external-labels`
@@ -40,6 +45,11 @@ with more recent data.
 
 More details can be found [here](querying/basics.md#offset-modifier).
 
+This feature is considered stable, but since it breaks the invariant that
+PromQL does not look ahead of the evaluation time, it still needs to be enabled
+via this feature flag. The feature will be permanently enabled (and the feature
+flag ignored) upon major release v3.
+
 ## Remote Write Receiver
 
 `--enable-feature=remote-write-receiver`