diff --git a/rattail_corepos/corepos/office/importing/db/model.py b/rattail_corepos/corepos/office/importing/db/model.py
index 96ba752..80e78e5 100644
--- a/rattail_corepos/corepos/office/importing/db/model.py
+++ b/rattail_corepos/corepos/office/importing/db/model.py
@@ -2,7 +2,7 @@
 ################################################################################
 #
 #  Rattail -- Retail Software Framework
-#  Copyright © 2010-2023 Lance Edgar
+#  Copyright © 2010-2024 Lance Edgar
 #
 #  This file is part of Rattail.
 #
@@ -163,6 +163,30 @@ class CustomerClassicImporter(ToCore):
     model_class = corepos.CustomerClassic
     key = 'id'
 
+    def setup(self):
+        super().setup()
+        self.common_setup()
+
+    def datasync_setup(self):
+        super().datasync_setup()
+        self.common_setup()
+
+    def common_setup(self):
+        if 'blue_line' in self.fields:
+            self.maxlen_blue_line = self.app.maxlen(corepos.CustomerClassic.blue_line)
+
+    def update_object(self, customer, data, local_data=None):
+
+        if 'blue_line' in self.fields:
+            blue_line = data['blue_line']
+            if blue_line and len(blue_line) > self.maxlen_blue_line:
+                log.warning("blue_line value is %s chars but will be truncated to %s: %s",
+                            len(blue_line), self.maxlen_blue_line, blue_line)
+                data['blue_line'] = blue_line[:self.maxlen_blue_line]
+
+        customer = super().update_object(customer, data, local_data=local_data)
+        return customer
+
 
 class MemberTypeImporter(ToCore):
     model_class = corepos.MemberType