diff --git a/routing/endpointregistry.go b/routing/endpointregistry.go
index c8f929d07a..f7840e034d 100644
--- a/routing/endpointregistry.go
+++ b/routing/endpointregistry.go
@@ -33,6 +33,7 @@ func (e *entry) InflightRequests() int64 {
 
 type EndpointRegistry struct {
 	lastSeen map[string]time.Time
+	now      func() time.Time
 
 	mu sync.Mutex
 
@@ -45,7 +46,7 @@ type RegistryOptions struct {
 }
 
 func (r *EndpointRegistry) Do(routes []*Route) []*Route {
-	now := time.Now()
+	now := r.now()
 
 	for _, route := range routes {
 		if route.BackendType == eskip.LBBackend {
@@ -76,6 +77,7 @@ func NewEndpointRegistry(o RegistryOptions) *EndpointRegistry {
 	return &EndpointRegistry{
 		data:     map[string]*entry{},
 		lastSeen: map[string]time.Time{},
+		now:      time.Now,
 	}
 }
 
diff --git a/routing/endpointregistry_test.go b/routing/endpointregistry_test.go
index 39c4d6e1c7..22039b9686 100644
--- a/routing/endpointregistry_test.go
+++ b/routing/endpointregistry_test.go
@@ -1,4 +1,4 @@
-package routing
+package routing_test
 
 import (
 	"fmt"
@@ -9,10 +9,11 @@ import (
 
 	"github.com/stretchr/testify/assert"
 	"github.com/zalando/skipper/eskip"
+	"github.com/zalando/skipper/routing"
 )
 
 func TestEmptyRegistry(t *testing.T) {
-	r := NewEndpointRegistry(RegistryOptions{})
+	r := routing.NewEndpointRegistry(routing.RegistryOptions{})
 	m := r.GetMetrics("some key")
 
 	assert.Equal(t, time.Time{}, m.DetectedTime())
@@ -20,7 +21,7 @@ func TestEmptyRegistry(t *testing.T) {
 }
 
 func TestSetAndGet(t *testing.T) {
-	r := NewEndpointRegistry(RegistryOptions{})
+	r := routing.NewEndpointRegistry(routing.RegistryOptions{})
 
 	mBefore := r.GetMetrics("some key")
 	r.IncInflightRequest("some key")
@@ -39,7 +40,7 @@ func TestSetAndGet(t *testing.T) {
 }
 
 func TestSetAndGetAnotherKey(t *testing.T) {
-	r := NewEndpointRegistry(RegistryOptions{})
+	r := routing.NewEndpointRegistry(routing.RegistryOptions{})
 
 	r.IncInflightRequest("some key")
 	mToChange := r.GetMetrics("some key")
@@ -50,20 +51,46 @@ func TestSetAndGetAnotherKey(t *testing.T) {
 }
 
 func TestDoRemovesOldEntries(t *testing.T) {
-	route := &Route{LBEndpoints: []LBEndpoint{
-		{Host: "existing endpoint"},
-	}}
-	route.BackendType = eskip.LBBackend
+	r := routing.NewEndpointRegistry(routing.RegistryOptions{})
 
-	r := NewEndpointRegistry(RegistryOptions{})
+	routing.SetNow(r, func() time.Time {
+		return time.Date(2023, 9, 14, 0, 0, 0, 0, time.UTC)
+	})
+	route := &routing.Route{
+		LBEndpoints: []routing.LBEndpoint{
+			{Host: "endpoint1.test:80"},
+			{Host: "endpoint2.test:80"},
+		},
+		Route: eskip.Route{
+			BackendType: eskip.LBBackend,
+		},
+	}
+	r.Do([]*routing.Route{route})
+
+	mExist := r.GetMetrics("endpoint1.test:80")
+	mExistYet := r.GetMetrics("endpoint2.test:80")
+	assert.NotEqual(t, time.Time{}, mExist.DetectedTime())
+	assert.NotEqual(t, time.Time{}, mExistYet.DetectedTime())
 
-	r.IncInflightRequest("existing endpoint")
-	r.IncInflightRequest("removed endpoint")
-	r.lastSeen["removed endpoint"] = time.Now().Add(-lastSeenTimeout)
-	r.Do([]*Route{route})
+	r.IncInflightRequest("endpoint1.test:80")
+	r.IncInflightRequest("endpoint2.test:80")
+
+	routing.SetNow(r, func() time.Time {
+		return time.Date(2023, 9, 14, 0, 0, 0, 0, time.UTC).Add(routing.ExportLastSeenTimeout + time.Second)
+	})
+	route = &routing.Route{
+		LBEndpoints: []routing.LBEndpoint{
+			{Host: "endpoint1.test:80"},
+		},
+		Route: eskip.Route{
+			BackendType: eskip.LBBackend,
+		},
+	}
+	route.BackendType = eskip.LBBackend
+	r.Do([]*routing.Route{route})
 
-	mExist := r.GetMetrics("existing endpoint")
-	mRemoved := r.GetMetrics("removed endpoint")
+	mExist = r.GetMetrics("endpoint1.test:80")
+	mRemoved := r.GetMetrics("endpoint2.test:80")
 
 	assert.NotEqual(t, time.Time{}, mExist.DetectedTime())
 	assert.Equal(t, int64(1), mExist.InflightRequests())
@@ -103,7 +130,7 @@ func benchmarkIncInflightRequests(b *testing.B, name string, goroutines int) {
 	const mapSize int = 10000
 
 	b.Run(name, func(b *testing.B) {
-		r := NewEndpointRegistry(RegistryOptions{})
+		r := routing.NewEndpointRegistry(routing.RegistryOptions{})
 		for i := 1; i < mapSize; i++ {
 			r.IncInflightRequest(fmt.Sprintf("foo-%d", i))
 		}
@@ -139,7 +166,7 @@ func benchmarkGetInflightRequests(b *testing.B, name string, goroutines int) {
 	const mapSize int = 10000
 
 	b.Run(name, func(b *testing.B) {
-		r := NewEndpointRegistry(RegistryOptions{})
+		r := routing.NewEndpointRegistry(routing.RegistryOptions{})
 		for i := 1; i < mapSize; i++ {
 			r.IncInflightRequest(fmt.Sprintf("foo-%d", i))
 		}
diff --git a/routing/export_test.go b/routing/export_test.go
index 174db04730..1049a10594 100644
--- a/routing/export_test.go
+++ b/routing/export_test.go
@@ -1,8 +1,15 @@
 package routing
 
+import "time"
+
 var (
 	ExportProcessRouteDef   = processRouteDef
 	ExportNewMatcher        = newMatcher
 	ExportMatch             = (*matcher).match
 	ExportProcessPredicates = processPredicates
+	ExportLastSeenTimeout   = lastSeenTimeout
 )
+
+func SetNow(r *EndpointRegistry, now func() time.Time) {
+	r.now = now
+}