diff --git a/pkg/source/pubsub/pubsub_source.go b/pkg/source/pubsub/pubsub_source.go
index 4d6cb98c..91af3c8f 100644
--- a/pkg/source/pubsub/pubsub_source.go
+++ b/pkg/source/pubsub/pubsub_source.go
@@ -85,9 +85,8 @@ func (f adapter) ProvideDefault() (interface{}, error) {
 	cfg := &Configuration{
 		// ConcurrentWrites:          50,
 		// Default is now handled in newPubsubSource, until we make a breaking release.
-		MaxOutstandingMessages:    1000,
-		MaxOutstandingBytes:       1e9,
-		MinExtensionPeriodSeconds: 0, // Default of 0 preserves client's default behaviour
+		MaxOutstandingMessages: 1000,
+		MaxOutstandingBytes:    1e9,
 		// StreamingPullGoRoutines:   1,
 		// Similarly handled in newPubsubSource - when we make a breaking release this should be the default.
 	}