diff --git a/docs/installation/upgrade-300.rst b/docs/installation/upgrade-300.rst
index 56ea34ff78..fd63aab7fa 100644
--- a/docs/installation/upgrade-300.rst
+++ b/docs/installation/upgrade-300.rst
@@ -130,3 +130,18 @@ The setting ``TEMPORARY_UPLOADS_REMOVED_AFTER_DAYS`` controls how long file uplo
 kept. Ensure that this many days have passed since the last legacy upload before
 upgrading to Open Forms 3.0, otherwise you will run into database errors during the
 upgrade.
+
+Deprecations in registration backends
+=====================================
+
+We've done extensive UX rework in the Objects API and ZGW API's registration backends -
+you can now select the case and/or document types to use in dropdowns rather than having
+to copy-paste the API resource URLs. The API resource URLs will continue to work and
+are scheduled for removal in Open Forms 4.0 (no planned date for this yet), but we
+recommend you to already migrate your forms to the new format:
+
+* it has a better UX for the people configuring forms :)
+* it automatically picks the correct version from the Catalogi API
+
+Migrating is as simple as opening the registration options, selecting the catalogue to
+use and then selecting the case type/document type to use and emptying the URL-field.
diff --git a/src/openforms/contrib/objects_api/models.py b/src/openforms/contrib/objects_api/models.py
index 3cb925129b..e1d3cd3a2a 100644
--- a/src/openforms/contrib/objects_api/models.py
+++ b/src/openforms/contrib/objects_api/models.py
@@ -141,7 +141,7 @@ class ObjectsAPIGroupConfig(models.Model):
     )
 
     # XXX: the URLFields are to be replaced with charfields storing the omschrijving.
-    # DeprecationWarning: remove in OF 3.0
+    # DeprecationWarning: remove in OF 4.0
     informatieobjecttype_submission_report = models.URLField(
         _("submission report informatieobjecttype"),
         max_length=1000,
diff --git a/src/openforms/registrations/contrib/objects_api/config.py b/src/openforms/registrations/contrib/objects_api/config.py
index e7c9d9143d..a405f0df14 100644
--- a/src/openforms/registrations/contrib/objects_api/config.py
+++ b/src/openforms/registrations/contrib/objects_api/config.py
@@ -175,7 +175,7 @@ class ObjectsAPIOptionsSerializer(JsonSchemaSerializerMixin, serializers.Seriali
         ),
     )
 
-    # DeprecationWarning: remove in OF 3.0
+    # DeprecationWarning: remove in OF 4.0
     informatieobjecttype_submission_report = serializers.URLField(
         label=_("submission report PDF informatieobjecttype"),
         help_text=_(
diff --git a/src/openforms/registrations/contrib/objects_api/typing.py b/src/openforms/registrations/contrib/objects_api/typing.py
index 00c0e624ca..779ac7fe1d 100644
--- a/src/openforms/registrations/contrib/objects_api/typing.py
+++ b/src/openforms/registrations/contrib/objects_api/typing.py
@@ -38,7 +38,7 @@ class _BaseRegistrationOptions(TypedDict, total=False):
     iot_submission_csv: Required[str]
     iot_attachment: Required[str]
 
-    # DeprecationWarning: URL properties will be removed in OF 3.0
+    # DeprecationWarning: URL properties will be removed in OF 4.0
     informatieobjecttype_submission_report: str
     informatieobjecttype_submission_csv: str
     informatieobjecttype_attachment: str
diff --git a/src/openforms/registrations/contrib/zgw_apis/options.py b/src/openforms/registrations/contrib/zgw_apis/options.py
index 9bca9766e0..11a150c62e 100644
--- a/src/openforms/registrations/contrib/zgw_apis/options.py
+++ b/src/openforms/registrations/contrib/zgw_apis/options.py
@@ -96,7 +96,7 @@ class ZaakOptionsSerializer(JsonSchemaSerializerMixin, serializers.Serializer):
         default="",
     )
 
-    # DeprecationWarning - deprecated, will be removed in OF 3.0 or 4.0
+    # DeprecationWarning - deprecated, will be removed in OF 4.0
     zaaktype = serializers.URLField(
         help_text=_("URL of the ZAAKTYPE in the Catalogi API"),
         required=False,