diff --git a/.github/workflows/sessions.yml b/.github/workflows/sessions.yml
index b0b08c465b3..26d6e30518b 100644
--- a/.github/workflows/sessions.yml
+++ b/.github/workflows/sessions.yml
@@ -26,7 +26,7 @@ jobs:
         target: [ios, tvos, macos, watchos]
         build-env:
           - os: macos-14
-            xcode: Xcode_15.3
+            xcode: Xcode_16.2
             tests:
           # Flaky tests on CI
           - os: macos-15
@@ -51,11 +51,13 @@ jobs:
   spm-package-resolved:
     env:
       FIREBASECI_USE_LATEST_GOOGLEAPPMEASUREMENT: 1
-    runs-on: macos-14
+    runs-on: macos-15
     outputs:
       cache_key: ${{ steps.generate_cache_key.outputs.cache_key }}
     steps:
       - uses: actions/checkout@v4
+      - name: Xcode
+        run: sudo xcode-select -s /Applications/Xcode_16.2.app/Contents/Developer
       - name: Generate Swift Package.resolved
         id: swift_package_resolve
         run: |
@@ -78,11 +80,8 @@ jobs:
     strategy:
       matrix:
         include:
-          - os: macos-13
-            xcode: Xcode_15.2
-            target: iOS
           - os: macos-14
-            xcode: Xcode_15.4
+            xcode: Xcode_16.2
             target: iOS
           - os: macos-15
             xcode: Xcode_16.2
diff --git a/FirebaseSessions/Sources/ApplicationInfo.swift b/FirebaseSessions/Sources/ApplicationInfo.swift
index cabc80d70f6..b298bd5550a 100644
--- a/FirebaseSessions/Sources/ApplicationInfo.swift
+++ b/FirebaseSessions/Sources/ApplicationInfo.swift
@@ -15,16 +15,16 @@
 
 import Foundation
 
-@_implementationOnly import FirebaseCore
+internal import FirebaseCore
 
 #if SWIFT_PACKAGE
   import FirebaseSessionsObjC
 #endif // SWIFT_PACKAGE
 
 #if SWIFT_PACKAGE
-  @_implementationOnly import GoogleUtilities_Environment
+  internal import GoogleUtilities_Environment
 #else
-  @_implementationOnly import GoogleUtilities
+  internal import GoogleUtilities
 #endif // SWIFT_PACKAGE
 
 /// Development environment for the application.
diff --git a/FirebaseSessions/Sources/EventGDTLogger.swift b/FirebaseSessions/Sources/EventGDTLogger.swift
index 03dff7d401f..20070706ae5 100644
--- a/FirebaseSessions/Sources/EventGDTLogger.swift
+++ b/FirebaseSessions/Sources/EventGDTLogger.swift
@@ -15,7 +15,7 @@
 
 import Foundation
 
-@_implementationOnly import GoogleDataTransport
+internal import GoogleDataTransport
 
 protocol EventGDTLoggerProtocol {
   func logEvent(event: SessionStartEvent, completion: @escaping (Result<Void, Error>) -> Void)
diff --git a/FirebaseSessions/Sources/FirebaseSessions.swift b/FirebaseSessions/Sources/FirebaseSessions.swift
index 2358f586404..be057cfc50f 100644
--- a/FirebaseSessions/Sources/FirebaseSessions.swift
+++ b/FirebaseSessions/Sources/FirebaseSessions.swift
@@ -15,16 +15,16 @@
 import Foundation
 
 // Avoids exposing internal FirebaseCore APIs to Swift users.
-@_implementationOnly import FirebaseCoreExtension
-@_implementationOnly import FirebaseInstallations
-@_implementationOnly import GoogleDataTransport
+internal import FirebaseCoreExtension
+internal import FirebaseInstallations
+internal import GoogleDataTransport
 
 #if swift(>=6.0)
   internal import Promises
 #elseif swift(>=5.10)
   import Promises
 #else
-  @_implementationOnly import Promises
+  internal import Promises
 #endif
 
 private enum GoogleDataTransportConfig {
diff --git a/FirebaseSessions/Sources/GoogleDataTransport+GoogleDataTransportProtocol.swift b/FirebaseSessions/Sources/GoogleDataTransport+GoogleDataTransportProtocol.swift
index 9c04f9c9ba2..b194b736ba4 100644
--- a/FirebaseSessions/Sources/GoogleDataTransport+GoogleDataTransportProtocol.swift
+++ b/FirebaseSessions/Sources/GoogleDataTransport+GoogleDataTransportProtocol.swift
@@ -15,7 +15,7 @@
 
 import Foundation
 
-@_implementationOnly import GoogleDataTransport
+internal import GoogleDataTransport
 
 enum GoogleDataTransportProtocolErrors: Error {
   case writeFailure
diff --git a/FirebaseSessions/Sources/Installations+InstallationsProtocol.swift b/FirebaseSessions/Sources/Installations+InstallationsProtocol.swift
index 6a467523e0c..04f30b3ad75 100644
--- a/FirebaseSessions/Sources/Installations+InstallationsProtocol.swift
+++ b/FirebaseSessions/Sources/Installations+InstallationsProtocol.swift
@@ -15,7 +15,7 @@
 
 import Foundation
 
-@_implementationOnly import FirebaseInstallations
+internal import FirebaseInstallations
 
 protocol InstallationsProtocol {
   var installationsWaitTimeInSecond: Int { get }
diff --git a/FirebaseSessions/Sources/Logger.swift b/FirebaseSessions/Sources/Logger.swift
index 513a83b1580..a8a3b3e7e2b 100644
--- a/FirebaseSessions/Sources/Logger.swift
+++ b/FirebaseSessions/Sources/Logger.swift
@@ -15,7 +15,7 @@
 
 import Foundation
 
-@_implementationOnly import FirebaseCoreExtension
+internal import FirebaseCoreExtension
 
 ///
 /// Logger is responsible for printing console logs
diff --git a/FirebaseSessions/Sources/NetworkInfo.swift b/FirebaseSessions/Sources/NetworkInfo.swift
index a24d36e98af..a197f3d75ff 100644
--- a/FirebaseSessions/Sources/NetworkInfo.swift
+++ b/FirebaseSessions/Sources/NetworkInfo.swift
@@ -20,9 +20,9 @@ import Foundation
 #endif // SWIFT_PACKAGE
 
 #if SWIFT_PACKAGE
-  @_implementationOnly import GoogleUtilities_Environment
+  internal import GoogleUtilities_Environment
 #else
-  @_implementationOnly import GoogleUtilities
+  internal import GoogleUtilities
 #endif // SWIFT_PACKAGE
 
 protocol NetworkInfoProtocol {
diff --git a/FirebaseSessions/Sources/SessionGenerator.swift b/FirebaseSessions/Sources/SessionGenerator.swift
index bbd6e59662a..a237f879710 100644
--- a/FirebaseSessions/Sources/SessionGenerator.swift
+++ b/FirebaseSessions/Sources/SessionGenerator.swift
@@ -15,7 +15,7 @@
 
 import Foundation
 
-@_implementationOnly import FirebaseInstallations
+internal import FirebaseInstallations
 
 struct SessionInfo {
   let sessionId: String
diff --git a/FirebaseSessions/Sources/SessionStartEvent.swift b/FirebaseSessions/Sources/SessionStartEvent.swift
index eb1560a86f5..8b3929054fc 100644
--- a/FirebaseSessions/Sources/SessionStartEvent.swift
+++ b/FirebaseSessions/Sources/SessionStartEvent.swift
@@ -15,16 +15,16 @@
 
 import Foundation
 
-@_implementationOnly import GoogleDataTransport
+internal import GoogleDataTransport
 
 #if SWIFT_PACKAGE
   import FirebaseSessionsObjC
 #endif // SWIFT_PACKAGE
 
 #if SWIFT_PACKAGE
-  @_implementationOnly import GoogleUtilities_Environment
+  internal import GoogleUtilities_Environment
 #else
-  @_implementationOnly import GoogleUtilities
+  internal import GoogleUtilities
 #endif // SWIFT_PACKAGE
 
 ///
diff --git a/FirebaseSessions/Sources/Settings/SettingsCacheClient.swift b/FirebaseSessions/Sources/Settings/SettingsCacheClient.swift
index f02b4dd17a6..52d222e46f7 100644
--- a/FirebaseSessions/Sources/Settings/SettingsCacheClient.swift
+++ b/FirebaseSessions/Sources/Settings/SettingsCacheClient.swift
@@ -16,9 +16,9 @@
 import Foundation
 
 #if SWIFT_PACKAGE
-  @_implementationOnly import GoogleUtilities_UserDefaults
+  internal import GoogleUtilities_UserDefaults
 #else
-  @_implementationOnly import GoogleUtilities
+  internal import GoogleUtilities
 #endif // SWIFT_PACKAGE
 
 /// CacheKey is like a "key" to a "safe". It provides necessary metadata about the current cache to
diff --git a/FirebaseSessions/Sources/Settings/SettingsDownloadClient.swift b/FirebaseSessions/Sources/Settings/SettingsDownloadClient.swift
index 66cda8defc0..dbfd7b2a666 100644
--- a/FirebaseSessions/Sources/Settings/SettingsDownloadClient.swift
+++ b/FirebaseSessions/Sources/Settings/SettingsDownloadClient.swift
@@ -16,9 +16,9 @@
 import Foundation
 
 #if SWIFT_PACKAGE
-  @_implementationOnly import GoogleUtilities_Environment
+  internal import GoogleUtilities_Environment
 #else
-  @_implementationOnly import GoogleUtilities
+  internal import GoogleUtilities
 #endif // SWIFT_PACKAGE
 
 protocol SettingsDownloadClient {
diff --git a/FirebaseSessions/Tests/TestApp/Shared/MockSubscriberSDK.swift b/FirebaseSessions/Tests/TestApp/Shared/MockSubscriberSDK.swift
index 2356fe570bf..c9a59e89f2b 100644
--- a/FirebaseSessions/Tests/TestApp/Shared/MockSubscriberSDK.swift
+++ b/FirebaseSessions/Tests/TestApp/Shared/MockSubscriberSDK.swift
@@ -17,7 +17,7 @@ import FirebaseSessions
 import Foundation
 
 // Avoids exposing internal FirebaseCore APIs to Swift users.
-@_implementationOnly import FirebaseCoreExtension
+internal import FirebaseCoreExtension
 
 @objc(FIRMockSubscriberSDKProtocol)
 protocol MockSubscriberSDKProtocol {
diff --git a/FirebaseSessions/Tests/Unit/Mocks/MockApplicationInfo.swift b/FirebaseSessions/Tests/Unit/Mocks/MockApplicationInfo.swift
index 4ca1010cd54..fea2bfc5cfd 100644
--- a/FirebaseSessions/Tests/Unit/Mocks/MockApplicationInfo.swift
+++ b/FirebaseSessions/Tests/Unit/Mocks/MockApplicationInfo.swift
@@ -16,9 +16,9 @@
 import Foundation
 
 #if SWIFT_PACKAGE
-  @_implementationOnly import GoogleUtilities_Environment
+  internal import GoogleUtilities_Environment
 #else
-  @_implementationOnly import GoogleUtilities
+  internal import GoogleUtilities
 #endif // SWIFT_PACKAGE
 
 @testable import FirebaseSessions
diff --git a/FirebaseSessions/Tests/Unit/Mocks/MockInstallationsProtocol.swift b/FirebaseSessions/Tests/Unit/Mocks/MockInstallationsProtocol.swift
index 10f9392776a..e61f492e8df 100644
--- a/FirebaseSessions/Tests/Unit/Mocks/MockInstallationsProtocol.swift
+++ b/FirebaseSessions/Tests/Unit/Mocks/MockInstallationsProtocol.swift
@@ -13,7 +13,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-@_implementationOnly import FirebaseInstallations
+internal import FirebaseInstallations
 
 @testable import FirebaseSessions
 
diff --git a/FirebaseSessions/Tests/Unit/Mocks/MockNetworkInfo.swift b/FirebaseSessions/Tests/Unit/Mocks/MockNetworkInfo.swift
index 2a8380dfbfb..103434179dc 100644
--- a/FirebaseSessions/Tests/Unit/Mocks/MockNetworkInfo.swift
+++ b/FirebaseSessions/Tests/Unit/Mocks/MockNetworkInfo.swift
@@ -16,9 +16,9 @@
 import Foundation
 
 #if SWIFT_PACKAGE
-  @_implementationOnly import GoogleUtilities_Environment
+  internal import GoogleUtilities_Environment
 #else
-  @_implementationOnly import GoogleUtilities
+  internal import GoogleUtilities
 #endif // SWIFT_PACKAGE
 
 @testable import FirebaseSessions
diff --git a/FirebaseSessions/Tests/Unit/SessionStartEventTests.swift b/FirebaseSessions/Tests/Unit/SessionStartEventTests.swift
index 21d5b5a2da5..edd169596f5 100644
--- a/FirebaseSessions/Tests/Unit/SessionStartEventTests.swift
+++ b/FirebaseSessions/Tests/Unit/SessionStartEventTests.swift
@@ -20,9 +20,9 @@ import XCTest
 #endif // SWIFT_PACKAGE
 
 #if SWIFT_PACKAGE
-  @_implementationOnly import GoogleUtilities_Environment
+  internal import GoogleUtilities_Environment
 #else
-  @_implementationOnly import GoogleUtilities
+  internal import GoogleUtilities
 #endif // SWIFT_PACKAGE
 
 @testable import FirebaseSessions