diff --git a/echolot-app/app/src/main/AndroidManifest.xml b/echolot-app/app/src/main/AndroidManifest.xml
index 130cfdb..87da644 100644
--- a/echolot-app/app/src/main/AndroidManifest.xml
+++ b/echolot-app/app/src/main/AndroidManifest.xml
@@ -22,7 +22,8 @@
 
         <activity
             android:name=".MainActivity"
-            android:exported="true">
+            android:exported="true"
+            android:launchMode="singleTask">
             <intent-filter>
                 <action android:name="android.intent.action.MAIN" />
                 <category android:name="android.intent.category.LAUNCHER" />
diff --git a/echolot-app/app/src/main/kotlin/app/echo_lot/app/MainActivity.kt b/echolot-app/app/src/main/kotlin/app/echo_lot/app/MainActivity.kt
index 3bd25cc..04cd61a 100644
--- a/echolot-app/app/src/main/kotlin/app/echo_lot/app/MainActivity.kt
+++ b/echolot-app/app/src/main/kotlin/app/echo_lot/app/MainActivity.kt
@@ -43,9 +43,27 @@ class MainActivity : ComponentActivity() {
     private val permissionLauncher =
         registerForActivityResult(ActivityResultContracts.RequestMultiplePermissions()) { /* proceed regardless */ }
 
+    /**
+     * The intent currently being acted on, so a deep link that arrives while the app is running
+     * is seen by the screen the user is already looking at.
+     *
+     * The activity is singleTask for the same reason. As a standard activity it stacked a second
+     * instance per link, each with its own ViewModel: the enrolment then happened in a throwaway
+     * copy, and pressing back returned to the original screen showing none of it. Silent, and
+     * indistinguishable from the link simply not working.
+     */
+    private val liveIntent = mutableStateOf<android.content.Intent?>(null)
+
+    override fun onNewIntent(intent: android.content.Intent) {
+        super.onNewIntent(intent)
+        setIntent(intent)
+        liveIntent.value = intent
+    }
+
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
         requestRuntimePermissions()
+        liveIntent.value = intent
         setContent {
             MaterialTheme(colorScheme = darkColorScheme()) {
                 Surface(color = MaterialTheme.colorScheme.background) {
@@ -66,7 +84,7 @@ class MainActivity : ComponentActivity() {
                     // Both deep links land here. They are told apart by host, so a sign-in
                     // redirect is never mistaken for an enrolment link — one spends a token, the
                     // other completes an authorization, and confusing them would fail obscurely.
-                    val incoming = intent?.takeIf { it.action == Intent.ACTION_VIEW }?.dataString
+                    val incoming = liveIntent.value?.takeIf { it.action == Intent.ACTION_VIEW }?.dataString
                     val authUri = incoming?.takeIf { it.startsWith("echolot://auth") }
                     val enrollUri = incoming?.takeIf { it.startsWith("echolot://enroll") }
                     androidx.compose.runtime.LaunchedEffect(enrollUri) {
@@ -80,21 +98,42 @@ class MainActivity : ComponentActivity() {
                     vm.state.pendingEnroll?.let { pending ->
                         androidx.compose.material3.AlertDialog(
                             onDismissRequest = { vm.cancelEnroll() },
-                            title = { androidx.compose.material3.Text("Replace this device's server?") },
+                            title = {
+                                androidx.compose.material3.Text(
+                                    if (pending.sameServer) "Enroll again with this server?"
+                                    else "Replace this device's server?"
+                                )
+                            },
                             text = {
                                 androidx.compose.material3.Text(
-                                    "This device is already enrolled with " +
-                                        "${pending.currentServer}.\n\n" +
-                                        "Enrolling with ${pending.newServer} replaces that. Runs " +
-                                        "already uploaded stay where they are, but this device " +
-                                        "stops reporting to the old server and appears on the new " +
-                                        "one as a new device.\n\n" +
-                                        "Runs stored on this phone are not affected."
+                                    // Naming the same URL twice reads as a mistake and buries the
+                                    // one consequence that actually applies: the device is issued a
+                                    // fresh credential and shows up as a second entry.
+                                    if (pending.sameServer) {
+                                        "This device is already enrolled with " +
+                                            "${pending.currentServer}.\n\n" +
+                                            "Enrolling again replaces its credential. The old one " +
+                                            "stops working immediately, and the device appears on " +
+                                            "the server as a new entry alongside the current one — " +
+                                            "which you may want to revoke afterwards.\n\n" +
+                                            "Runs already uploaded, and runs stored on this phone, " +
+                                            "are not affected."
+                                    } else {
+                                        "This device is already enrolled with " +
+                                            "${pending.currentServer}.\n\n" +
+                                            "Enrolling with ${pending.newServer} replaces that. Runs " +
+                                            "already uploaded stay where they are, but this device " +
+                                            "stops reporting to the old server and appears on the new " +
+                                            "one as a new device.\n\n" +
+                                            "Runs stored on this phone are not affected."
+                                    }
                                 )
                             },
                             confirmButton = {
                                 androidx.compose.material3.TextButton(onClick = { vm.confirmEnroll() }) {
-                                    androidx.compose.material3.Text("Enroll here")
+                                    androidx.compose.material3.Text(
+                                        if (pending.sameServer) "Enroll again" else "Enroll here"
+                                    )
                                 }
                             },
                             dismissButton = {
diff --git a/echolot-app/app/src/main/kotlin/app/echo_lot/app/RunViewModel.kt b/echolot-app/app/src/main/kotlin/app/echo_lot/app/RunViewModel.kt
index 8375415..be3c873 100644
--- a/echolot-app/app/src/main/kotlin/app/echo_lot/app/RunViewModel.kt
+++ b/echolot-app/app/src/main/kotlin/app/echo_lot/app/RunViewModel.kt
@@ -58,7 +58,10 @@ data class UiState(
  * device simply stops reporting. Following a link is one tap from a web page, which is not enough
  * deliberation to discard a working enrollment by accident.
  */
-data class PendingEnroll(val link: String, val currentServer: String, val newServer: String)
+data class PendingEnroll(val link: String, val currentServer: String, val newServer: String) {
+    /** Re-enrolling with the server already configured, rather than moving to a different one. */
+    val sameServer: Boolean get() = currentServer.trimEnd('/') == newServer.trimEnd('/')
+}
 
 /**
  * Drives one measurement run: device-tier probes (link snapshot, per-network ICMP) always run;