diff --git a/scripts/resume_sync.py b/scripts/resume_sync.py
index a6dfa38..d669ea9 100644
--- a/scripts/resume_sync.py
+++ b/scripts/resume_sync.py
@@ -122,9 +122,15 @@ def profile_to_library(payload: dict[str, Any]) -> tuple[str, dict[str, Any]]:
         period  = (exp.get("period") or "").strip()
         location = (exp.get("location") or "").strip()
 
-        # Split period back to start_date / end_date
-        sep_period = period.replace("\u2013", "-").replace("\u2014", "-")
-        date_parts = [p.strip() for p in sep_period.split("-", 1)]
+        # Split period back to start_date / end_date.
+        # Split on the dash/dash separator BEFORE normalising to plain hyphens
+        # so that ISO dates like "2023-01 – 2025-03" round-trip correctly.
+        if "\u2013" in period:          # en-dash
+            date_parts = [p.strip() for p in period.split("\u2013", 1)]
+        elif "\u2014" in period:        # em-dash
+            date_parts = [p.strip() for p in period.split("\u2014", 1)]
+        else:
+            date_parts = [period.strip()] if period.strip() else []
         start_date = date_parts[0] if date_parts else ""
         end_date   = date_parts[1] if len(date_parts) > 1 else ""
 
diff --git a/tests/test_resume_sync.py b/tests/test_resume_sync.py
index a35b1ba..fa41a67 100644
--- a/tests/test_resume_sync.py
+++ b/tests/test_resume_sync.py
@@ -139,6 +139,32 @@ def test_profile_to_library_period_split():
     assert struct["experience"][0]["start_date"] == "2023"
     assert struct["experience"][0]["end_date"] == "present"
 
+def test_profile_to_library_period_split_iso_dates():
+    """ISO dates (with hyphens) must round-trip through the period field correctly."""
+    payload = {
+        **PROFILE_PAYLOAD,
+        "experience": [{
+            **PROFILE_PAYLOAD["experience"][0],
+            "period": "2023-01 \u2013 2025-03",
+        }],
+    }
+    _, struct = profile_to_library(payload)
+    assert struct["experience"][0]["start_date"] == "2023-01"
+    assert struct["experience"][0]["end_date"] == "2025-03"
+
+def test_profile_to_library_period_split_em_dash():
+    """Em-dash separator is also handled."""
+    payload = {
+        **PROFILE_PAYLOAD,
+        "experience": [{
+            **PROFILE_PAYLOAD["experience"][0],
+            "period": "2022-06 \u2014 2023-12",
+        }],
+    }
+    _, struct = profile_to_library(payload)
+    assert struct["experience"][0]["start_date"] == "2022-06"
+    assert struct["experience"][0]["end_date"] == "2023-12"
+
 def test_profile_to_library_education_round_trip():
     _, struct = profile_to_library(PROFILE_PAYLOAD)
     assert struct["education"][0]["institution"] == "State University"