diff --git a/CHANGELOG.md b/CHANGELOG.md
index 0a727a13..041bed54 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -36,6 +36,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 - ES-CL: the ITACyL server is https-only, the 2025 shapefiles sit in province subfolders, and C_REFREC is the identifier
 - A test refuses a fixture above 5 MB, committed or merely lying in the fixture folder, because a failing convert test downloads the real source there
 - ES-MD: find RECINTO.shp wherever the archive puts it
+- ES-CM: read the year-named SIGPAC service, whose id field is OBJECTID_1, with the determination date from the variant
 - ES-CN: the seven island files each kept their own row index, and the region was declared as Cantabria
 - EC-EE: name the shapefile inside the archive, migrate the year column the release actually has, and require only what every parcel carries
 - ES-CAT: the 2024 download is a shapefile package, and 34 crop names new in that edition are mapped
diff --git a/fiboa_cli/datasets/es_cm.py b/fiboa_cli/datasets/es_cm.py
index 789ce436..ded133bb 100644
--- a/fiboa_cli/datasets/es_cm.py
+++ b/fiboa_cli/datasets/es_cm.py
@@ -8,7 +8,7 @@
 
 class ESCMConverter(EsriRESTConverterMixin, ESBaseConverter):
     id = "es_cm"
-    short_name = "Spain "
+    short_name = "Spain Castilla-La Mancha"
     title = "Spain Castilla-La Mancha Crop fields"
     description = """
 SIGPAC is a Geographic Information System dedicated to the control of agricultural aid under
@@ -19,16 +19,18 @@ class ESCMConverter(EsriRESTConverterMixin, ESBaseConverter):
     attribution = "Unidad de Cartografía. Secretaría General. Consejería de Agricultura, Ganadería y Desarrollo Rural."
     provider = "Unidad de Cartografía. Secretaría General. Consejería de Agricultura, Ganadería y Desarrollo Rural. <https://datosabiertos.castillalamancha.es>"
     columns = {
-        "dn_oid": "id",
+        "DN_OID": "id",
         "geometry": "geometry",
-        "provincia": "admin_province_code",
-        "municipio": "admin_municipality_code",
-        "dn_surface": "metrics:area",
-        "uso_sigpac": "crop:code",
+        "PROVINCIA": "admin_province_code",
+        "MUNICIPIO": "admin_municipality_code",
+        "DN_SURFACE": "metrics:area",
+        "USO_SIGPAC": "crop:code",
         "crop:name": "crop:name",
         "crop:name_en": "crop:name_en",
     }
+    use_code_attribute = "USO_SIGPAC"
     area_is_in_ha = False
+    use_variant_as_determination = True
     missing_schemas = {
         "properties": {
             "admin_province_code": {"type": "string"},
@@ -38,19 +40,17 @@ class ESCMConverter(EsriRESTConverterMixin, ESBaseConverter):
     variants = {str(year): str(year) for year in range(2024, 2018 - 1, -1)}
 
     rest_base_url = "https://geoservicios.castillalamancha.es/arcgis/rest/services/Vector"
-    rest_attribute = "objectid_1"
+    rest_attribute = "OBJECTID_1"
 
     def get_urls(self):
-        latest_year = next(iter(self.variants))
         if not self.variant:
-            self.variant = latest_year
-        if self.variant == latest_year:
-            layer = "Vector/Recintos_sigpac"
-        else:
-            services = requests.get(self.rest_base_url, {"f": "pjson"}).json()["services"]
-            layer = next(
-                s["name"]
-                for s in services
-                if re.search(f"Recintos_sigpac_{self.variant}", s["name"], re.IGNORECASE)
-            )
+            self.variant = next(iter(self.variants))
+        # Always use the year-named service: the unnamed "Recintos_sigpac" service is
+        # whatever year is current (2025 in August 2026) and keys on OBJECTID instead.
+        services = requests.get(self.rest_base_url, {"f": "pjson"}).json()["services"]
+        layer = next(
+            s["name"]
+            for s in services
+            if re.search(f"Recintos_sigpac_{self.variant}$", s["name"], re.IGNORECASE)
+        )
         return {"REST": self.rest_base_url.replace("Vector", layer + "/MapServer")}
diff --git a/tests/data-files/convert/es_cm/es_cm_0.gpkg b/tests/data-files/convert/es_cm/es_cm_0.gpkg
new file mode 100644
index 00000000..d99d2891
Binary files /dev/null and b/tests/data-files/convert/es_cm/es_cm_0.gpkg differ
diff --git a/tests/test_convert.py b/tests/test_convert.py
index 9af3eb30..df46fb89 100644
--- a/tests/test_convert.py
+++ b/tests/test_convert.py
@@ -46,6 +46,7 @@
     "ie",
     "es_cat",
     "es_cl",
+    "es_cm",
     "es",
     "nz",
     "lt",
@@ -85,6 +86,7 @@ def _input_files(converter, *names):
         "variant": "2025",
         "input_files": {f"{test_path}/es_cl/AVILA.zip": ["replaceme.zip"]},
     },
+    "es_cm": {"variant": "2024", **_input_files("es_cm", "es_cm_0.gpkg")},
     "es_an": {
         "variant": "2025",
         "input_files": {f"{test_path}/es_an/SP25_REC_PROV_04.zip": ["SP25_REC_04.shp"]},