diff --git a/app-k9mail/build.gradle.kts b/app-k9mail/build.gradle.kts
index c228f740c3..48a12adc65 100644
--- a/app-k9mail/build.gradle.kts
+++ b/app-k9mail/build.gradle.kts
@@ -106,7 +106,7 @@ android {
     }
 
     signingConfigs {
-        createSigningConfig(project, SigningType.K9_RELEASE)
+        createSigningConfig(project, SigningType.K9_RELEASE, isUpload = false)
     }
 
     buildTypes {
diff --git a/app-thunderbird/build.gradle.kts b/app-thunderbird/build.gradle.kts
index 0414be744c..eff83a9c99 100644
--- a/app-thunderbird/build.gradle.kts
+++ b/app-thunderbird/build.gradle.kts
@@ -42,7 +42,7 @@ android {
         applicationId = "net.thunderbird.android"
         testApplicationId = "net.thunderbird.android.tests"
 
-        versionCode = 1
+        versionCode = 2
         versionName = "0.1"
 
         // Keep in sync with the resource string array "supported_languages"
@@ -117,6 +117,8 @@ android {
             versionNameSuffix = "-SNAPSHOT"
 
             isMinifyEnabled = false
+            isShrinkResources = false
+            isDebuggable = true
         }
 
         release {
@@ -124,6 +126,7 @@ android {
 
             isMinifyEnabled = true
             isShrinkResources = true
+            isDebuggable = false
 
             proguardFiles(
                 getDefaultProguardFile("proguard-android.txt"),
@@ -132,25 +135,39 @@ android {
         }
 
         create("beta") {
-            initWith(getByName("release"))
-
             signingConfig = signingConfigs.getByType(SigningType.TB_BETA)
 
             applicationIdSuffix = ".beta"
             versionNameSuffix = "b1"
 
+            isMinifyEnabled = true
+            isShrinkResources = true
+            isDebuggable = false
+
             matchingFallbacks += listOf("release")
+
+            proguardFiles(
+                getDefaultProguardFile("proguard-android.txt"),
+                "proguard-rules.pro",
+            )
         }
 
         create("daily") {
-            initWith(getByName("release"))
-
             signingConfig = signingConfigs.getByType(SigningType.TB_DAILY)
 
             applicationIdSuffix = ".daily"
             versionNameSuffix = "a1"
 
+            isMinifyEnabled = true
+            isShrinkResources = true
+            isDebuggable = false
+
             matchingFallbacks += listOf("release")
+
+            proguardFiles(
+                getDefaultProguardFile("proguard-android.txt"),
+                "proguard-rules.pro",
+            )
         }
     }
 
diff --git a/build-plugin/src/main/kotlin/SigningExtensions.kt b/build-plugin/src/main/kotlin/SigningExtensions.kt
index 284828244b..98dda8297d 100644
--- a/build-plugin/src/main/kotlin/SigningExtensions.kt
+++ b/build-plugin/src/main/kotlin/SigningExtensions.kt
@@ -6,6 +6,7 @@ import org.gradle.api.Project
 
 private const val SIGNING_FOLDER = ".signing"
 private const val SIGNING_FILE_ENDING = ".signing.properties"
+private const val UPLOAD_FILE_ENDING = ".upload.properties"
 
 private const val PROPERTY_STORE_FILE = "storeFile"
 private const val PROPERTY_STORE_PASSWORD = "storePassword"
@@ -16,7 +17,7 @@ private const val PROPERTY_KEY_PASSWORD = "keyPassword"
  * Creates an [ApkSigningConfig] for the given signing type.
  *
  * The signing properties are read from a file in the `.signing` folder in the project root directory.
- * File names are expected to be in the format `$app.$type.signing.properties`.
+ * File names are expected to be in the format `$app.$type.signing.properties` or `$app.$type.upload.properties`.
  *
  * The file should contain the following properties:
  * - `$app.$type.storeFile`
@@ -26,9 +27,14 @@ private const val PROPERTY_KEY_PASSWORD = "keyPassword"
  *
  * @param project the project to create the signing config for
  * @param signingType the signing type to create the signing config for
+ * @param isUpload whether the upload or signing config is used
  */
-fun NamedDomainObjectContainer<out ApkSigningConfig>.createSigningConfig(project: Project, signingType: SigningType) {
-    val properties = project.readSigningProperties(signingType)
+fun NamedDomainObjectContainer<out ApkSigningConfig>.createSigningConfig(
+    project: Project,
+    signingType: SigningType,
+    isUpload: Boolean = true,
+) {
+    val properties = project.readSigningProperties(signingType, isUpload)
 
     if (properties.hasSigningConfig(signingType)) {
         create(signingType.type) {
@@ -37,6 +43,8 @@ fun NamedDomainObjectContainer<out ApkSigningConfig>.createSigningConfig(project
             keyAlias = properties.getSigningProperty(signingType, PROPERTY_KEY_ALIAS)
             keyPassword = properties.getSigningProperty(signingType, PROPERTY_KEY_PASSWORD)
         }
+    } else {
+        println("Signing config not created for ${signingType.type}")
     }
 }
 
@@ -49,8 +57,13 @@ fun NamedDomainObjectContainer<out ApkSigningConfig>.getByType(signingType: Sign
     return findByName(signingType.type)
 }
 
-private fun Project.readSigningProperties(signingType: SigningType) = Properties().apply {
-    val signingPropertiesFile = rootProject.file("$SIGNING_FOLDER/${signingType.id}$SIGNING_FILE_ENDING")
+private fun Project.readSigningProperties(signingType: SigningType, isUpload: Boolean) = Properties().apply {
+    val signingPropertiesFile = if (isUpload) {
+        rootProject.file("$SIGNING_FOLDER/${signingType.id}$UPLOAD_FILE_ENDING")
+    } else {
+        rootProject.file("$SIGNING_FOLDER/${signingType.id}$SIGNING_FILE_ENDING")
+    }
+
     if (signingPropertiesFile.exists()) {
         FileInputStream(signingPropertiesFile).use { inputStream ->
             load(inputStream)