diff --git a/src/firebase_functions/identity_fn.py b/src/firebase_functions/identity_fn.py
index 9a8d18f..8e84c73 100644
--- a/src/firebase_functions/identity_fn.py
+++ b/src/firebase_functions/identity_fn.py
@@ -59,7 +59,7 @@ class AuthUserMetadata:
     creation_time: _dt.datetime
     """The date the user was created."""
 
-    last_sign_in_time: _dt.datetime
+    last_sign_in_time: _typing.Optional[_dt.datetime]
     """The date the user last signed in."""
 
 
diff --git a/src/firebase_functions/private/_identity_fn.py b/src/firebase_functions/private/_identity_fn.py
index e301141..dc7d169 100644
--- a/src/firebase_functions/private/_identity_fn.py
+++ b/src/firebase_functions/private/_identity_fn.py
@@ -64,12 +64,15 @@ def _auth_user_info_from_token_data(token_data: dict[str, _typing.Any]):
 
 def _auth_user_metadata_from_token_data(token_data: dict[str, _typing.Any]):
     from firebase_functions.identity_fn import AuthUserMetadata
-    return AuthUserMetadata(
-        creation_time=_dt.datetime.utcfromtimestamp(
-            token_data["creation_time"] / 1000.0),
-        last_sign_in_time=_dt.datetime.utcfromtimestamp(
-            token_data["last_sign_in_time"] / 1000.0),
-    )
+    creation_time = _dt.datetime.utcfromtimestamp(
+        int(token_data["creation_time"]) / 1000.0)
+    last_sign_in_time = None
+    if "last_sign_in_time" in token_data:
+        last_sign_in_time = _dt.datetime.utcfromtimestamp(
+            int(token_data["last_sign_in_time"]) / 1000.0)
+
+    return AuthUserMetadata(creation_time=creation_time,
+                            last_sign_in_time=last_sign_in_time)
 
 
 def _auth_multi_factor_info_from_token_data(token_data: dict[str, _typing.Any]):
diff --git a/src/firebase_functions/private/token_verifier.py b/src/firebase_functions/private/token_verifier.py
index 300da43..a986ec4 100644
--- a/src/firebase_functions/private/token_verifier.py
+++ b/src/firebase_functions/private/token_verifier.py
@@ -95,14 +95,14 @@ def verify(self, token, request):
                 'Firebase {0} has incorrect algorithm. Expected "RS256" but got '
                 '"{1}". {2}'.format(self.short_name, header.get('alg'),
                                     verify_id_token_msg))
-        elif self.expected_audience and self.expected_audience not in audience:
+        elif not emulated and self.expected_audience and self.expected_audience not in audience:
             error_message = (
                 'Firebase {0} has incorrect "aud" (audience) claim. Expected "{1}" but '
                 'got "{2}". {3} {4}'.format(self.short_name,
                                             self.expected_audience, audience,
                                             project_id_match_msg,
                                             verify_id_token_msg))
-        elif not self.expected_audience and audience != self.project_id:
+        elif not emulated and not self.expected_audience and audience != self.project_id:
             error_message = (
                 'Firebase {0} has incorrect "aud" (audience) claim. Expected "{1}" but '
                 'got "{2}". {3} {4}'.format(self.short_name, self.project_id,