diff --git a/tests/device_tests/test_language.py b/tests/device_tests/test_language.py
index 1197b9752d..3322aa05cc 100644
--- a/tests/device_tests/test_language.py
+++ b/tests/device_tests/test_language.py
@@ -100,7 +100,7 @@ def test_error_invalid_data_length(client: Client):
     # Invalid data length
     # Sending more data than advertised in the header
     with pytest.raises(exceptions.TrezorFailure, match="Invalid data length"), client:
-        good_data = build_and_sign_blob("cs", client.model)
+        good_data = build_and_sign_blob("cs", client)
         bad_data = good_data + b"abcd"
         device.change_language(client, language_data=bad_data)
     assert client.features.language == "en-US"
@@ -114,7 +114,7 @@ def test_error_invalid_header_magic(client: Client):
     with pytest.raises(
         exceptions.TrezorFailure, match="Invalid translations data"
     ), client:
-        good_data = build_and_sign_blob("cs", client.model)
+        good_data = build_and_sign_blob("cs", client)
         bad_data = 4 * b"a" + good_data[4:]
         device.change_language(client, language_data=bad_data)
     assert client.features.language == "en-US"
@@ -128,7 +128,7 @@ def test_error_invalid_data_hash(client: Client):
     with pytest.raises(
         exceptions.TrezorFailure, match="Translation data verification failed"
     ), client:
-        good_data = build_and_sign_blob("cs", client.model)
+        good_data = build_and_sign_blob("cs", client)
         bad_data = good_data[:-8] + 8 * b"a"
         device.change_language(
             client,
@@ -145,11 +145,10 @@ def test_error_version_mismatch(client: Client):
     with pytest.raises(
         exceptions.TrezorFailure, match="Translations version mismatch"
     ), client:
-        data = get_lang_json("cs")
-        data["header"]["version"] = "3.5.4"
+        blob = prepare_blob("cs", client.model, (3, 5, 4, 0))
         device.change_language(
             client,
-            language_data=build_and_sign_blob(data, client.model),
+            language_data=sign_blob(blob),
         )
     assert client.features.language == "en-US"
     _check_ping_screen_texts(client, get_ping_title("en"), get_ping_button("en"))
@@ -221,7 +220,7 @@ def test_translations_renders_on_screen(client: Client):
     czech_data_copy["translations"]["words__confirm"] = new_czech_confirm
     device.change_language(
         client,
-        language_data=build_and_sign_blob(czech_data_copy, client.model),
+        language_data=build_and_sign_blob(czech_data_copy, client),
     )
     _check_ping_screen_texts(client, new_czech_confirm, get_ping_button("cs"))
 
@@ -230,7 +229,7 @@ def test_translations_renders_on_screen(client: Client):
     del czech_data_copy["translations"]["words__confirm"]
     device.change_language(
         client,
-        language_data=build_and_sign_blob(czech_data_copy, client.model),
+        language_data=build_and_sign_blob(czech_data_copy, client),
     )
     _check_ping_screen_texts(client, get_ping_title("en"), get_ping_button("cs"))
 
@@ -238,7 +237,7 @@ def test_translations_renders_on_screen(client: Client):
 def test_reject_update(client: Client):
     assert client.features.language == "en-US"
     lang = "cs"
-    language_data = build_and_sign_blob(lang, client.model)
+    language_data = build_and_sign_blob(lang, client)
 
     def input_flow_reject():
         yield
@@ -256,7 +255,7 @@ def test_reject_update(client: Client):
 def _maybe_confirm_set_language(
     client: Client, lang: str, show_display: bool | None, is_displayed: bool
 ) -> None:
-    language_data = build_and_sign_blob(lang, client.model)
+    language_data = build_and_sign_blob(lang, client)
 
     CHUNK_SIZE = 1024
 
@@ -356,7 +355,7 @@ def test_header_trailing_data(client: Client):
     """
     assert client.features.language == "en-US"
     lang = "cs"
-    blob = prepare_blob(lang, client.model)
+    blob = prepare_blob(lang, client.model, client.version)
     blob.header_bytes += b"trailing dataa"
     assert len(blob.header_bytes) % 2 == 0, "Trailing data must keep the 2-alignment"
     language_data = sign_blob(blob)
diff --git a/tests/translations.py b/tests/translations.py
index 6f45d134fb..c9be7881c5 100644
--- a/tests/translations.py
+++ b/tests/translations.py
@@ -22,6 +22,7 @@ LANGUAGES = [file.stem for file in TRANSLATIONS.glob("??.json")]
 def prepare_blob(
     lang_or_def: translations.JsonDef | Path | str,
     model: models.TrezorModel,
+    version: translations.VersionTuple | tuple[int, int, int] | None = None,
 ) -> translations.TranslationsBlob:
     order = translations.order_from_json(json.loads(ORDER_FILE.read_text()))
     if isinstance(lang_or_def, str):
@@ -30,7 +31,11 @@ def prepare_blob(
         lang_or_def = t.cast(translations.JsonDef, json.loads(lang_or_def.read_text()))
 
     # generate raw blob
-    version = translations.version_from_json(lang_or_def["header"]["version"])
+    if version is None:
+        version = translations.version_from_json(lang_or_def["header"]["version"])
+    elif len(version) == 3:
+        # version coming from client object does not have build item
+        version = *version, 0
     return translations.blob_from_defs(lang_or_def, order, model, version, FONTS_DIR)
 
 
@@ -48,9 +53,9 @@ def sign_blob(blob: translations.TranslationsBlob) -> bytes:
 
 def build_and_sign_blob(
     lang_or_def: translations.JsonDef | Path | str,
-    model: models.TrezorModel,
+    client: Client,
 ) -> bytes:
-    blob = prepare_blob(lang_or_def, model)
+    blob = prepare_blob(lang_or_def, client.model, client.version)
     return sign_blob(blob)
 
 
@@ -58,7 +63,7 @@ def set_language(client: Client, lang: str):
     if lang.startswith("en"):
         language_data = b""
     else:
-        language_data = build_and_sign_blob(lang, client.model)
+        language_data = build_and_sign_blob(lang, client)
     with client:
         device.change_language(client, language_data)  # type: ignore