diff --git a/apps/edr-freight-web/portal/src/pages/bookings/new-booking-form/step4-route.tsx b/apps/edr-freight-web/portal/src/pages/bookings/new-booking-form/step4-route.tsx
index 283315351..85453ccb5 100644
--- a/apps/edr-freight-web/portal/src/pages/bookings/new-booking-form/step4-route.tsx
+++ b/apps/edr-freight-web/portal/src/pages/bookings/new-booking-form/step4-route.tsx
@@ -19,7 +19,7 @@ import {
   Snowflake,
   Trash2,
 } from "lucide-react";
-import { useEffect, useMemo } from "react";
+import { useCallback, useEffect, useMemo } from "react";
 import {
   Controller,
   useFieldArray,
@@ -80,29 +80,39 @@ export function Step4Route({
     remove: removeRoute,
   } = useFieldArray({ control: form.control, name: "extraRoutes" });
 
+  // useFieldArray's `fields` don't re-render on value change, so watch the live
+  // route values to filter each row's yard options by what it has selected.
+  const watchedExtraRoutes = form.watch("extraRoutes") ?? [];
+
   const yardOptions = useMemo(() => {
     if (!referenceData?.yard) return [];
     return referenceData.yard.map((y) => ({ value: y.id, label: y.name }));
   }, [referenceData]);
 
-  const originData = useMemo(() => {
-    return yardOptions
-      .filter((o) => o.value !== destinationYard)
-      .filter((o) => {
-        if (!originCountry) return true;
-        const yard = referenceData?.yard.find((y) => y.id === o.value);
-        return yard?.country === originCountry;
-      });
-  }, [yardOptions, destinationYard, originCountry, referenceData]);
-  const destData = useMemo(() => {
-    return yardOptions
-      .filter((o) => o.value !== originYard)
-      .filter((o) => {
-        if (!destinationCountry) return true;
-        const yard = referenceData?.yard.find((y) => y.id === o.value);
-        return yard?.country === destinationCountry;
-      });
-  }, [yardOptions, originYard, destinationCountry, referenceData]);
+  // Filter the yard list to one side of a route: the yards in `country` (the
+  // operation type fixes which country each end must be in — see originCountry /
+  // destinationCountry above), excluding the yard already chosen on the other
+  // end of the same route so origin and destination can never match.
+  const yardsForSide = useCallback(
+    (country: string | null, excludeYardId: string) =>
+      yardOptions
+        .filter((o) => o.value !== excludeYardId)
+        .filter((o) => {
+          if (!country) return true;
+          const yard = referenceData?.yard.find((y) => y.id === o.value);
+          return yard?.country === country;
+        }),
+    [yardOptions, referenceData],
+  );
+
+  const originData = useMemo(
+    () => yardsForSide(originCountry, destinationYard),
+    [yardsForSide, originCountry, destinationYard],
+  );
+  const destData = useMemo(
+    () => yardsForSide(destinationCountry, originYard),
+    [yardsForSide, destinationCountry, originYard],
+  );
 
   const origin = referenceData?.yard.find((y) => y.id === originYard);
   const dest = referenceData?.yard.find((y) => y.id === destinationYard);
@@ -123,6 +133,25 @@ export function Step4Route({
     }
   }, [destinationCountry, dest, form]);
 
+  // Same cleanup for the extra contract routes: when the operation type changes,
+  // clear any extra-route yard whose country no longer matches the required side
+  // so an added route can't contradict the operation either.
+  useEffect(() => {
+    watchedExtraRoutes.forEach((route, i) => {
+      const ro = referenceData?.yard.find((y) => y.id === route?.originYard);
+      if (originCountry && ro && ro.country !== originCountry) {
+        form.setValue(`extraRoutes.${i}.originYard`, "");
+      }
+      const rd = referenceData?.yard.find(
+        (y) => y.id === route?.destinationYard,
+      );
+      if (destinationCountry && rd && rd.country !== destinationCountry) {
+        form.setValue(`extraRoutes.${i}.destinationYard`, "");
+      }
+    });
+    // eslint-disable-next-line react-hooks/exhaustive-deps
+  }, [originCountry, destinationCountry, referenceData, form]);
+
   const directionStyle: Record<string, string> = {
     EXPORT: "bg-sky-50 text-sky-800 border-sky-200",
     IMPORT: "bg-amber-50 text-amber-800 border-amber-200",
@@ -263,57 +292,70 @@ export function Step4Route({
             cover.
           </Text>
           <Stack gap={12}>
-            {extraRoutes.map((rf, i) => (
-              <Group
-                key={rf.id}
-                gap={10}
-                align="flex-start"
-                wrap="nowrap"
-                className="rounded-xl"
-                style={{ border: "1px solid #E6ECF2", padding: 12 }}
-              >
-                <Box style={{ flex: 1 }}>
-                  <Controller
-                    name={`extraRoutes.${i}.originYard`}
-                    control={form.control}
-                    render={({ field, fieldState }) => (
-                      <SelectField
-                        field={field}
-                        error={fieldState.error}
-                        label="Origin"
-                        placeholder="Origin..."
-                        data={yardOptions}
-                      />
-                    )}
-                  />
-                </Box>
-                <Box style={{ flex: 1 }}>
-                  <Controller
-                    name={`extraRoutes.${i}.destinationYard`}
-                    control={form.control}
-                    render={({ field, fieldState }) => (
-                      <SelectField
-                        field={field}
-                        error={fieldState.error}
-                        label="Destination"
-                        placeholder="Destination..."
-                        data={yardOptions}
-                      />
-                    )}
-                  />
-                </Box>
-                <Button
-                  variant="subtle"
-                  color="red"
-                  size="xs"
-                  mt={24}
-                  px={6}
-                  onClick={() => removeRoute(i)}
+            {extraRoutes.map((rf, i) => {
+              // Each extra route is constrained by the SAME operation type as the
+              // primary route: its origin must sit in originCountry and its
+              // destination in destinationCountry. Watch this row's current values
+              // so each side also excludes the yard picked on the other side.
+              const rowOrigin = watchedExtraRoutes[i]?.originYard ?? "";
+              const rowDestination =
+                watchedExtraRoutes[i]?.destinationYard ?? "";
+              const rowOriginData = yardsForSide(originCountry, rowDestination);
+              const rowDestData = yardsForSide(destinationCountry, rowOrigin);
+              return (
+                <Group
+                  key={rf.id}
+                  gap={10}
+                  align="flex-start"
+                  wrap="nowrap"
+                  className="rounded-xl"
+                  style={{ border: "1px solid #E6ECF2", padding: 12 }}
                 >
-                  <Trash2 size={16} />
-                </Button>
-              </Group>
-            ))}
+                  <Box style={{ flex: 1 }}>
+                    <Controller
+                      name={`extraRoutes.${i}.originYard`}
+                      control={form.control}
+                      render={({ field, fieldState }) => (
+                        <SelectField
+                          field={field}
+                          error={fieldState.error}
+                          label="Origin"
+                          placeholder="Origin..."
+                          disabled={stationSelectDisabled}
+                          data={rowOriginData}
+                        />
+                      )}
+                    />
+                  </Box>
+                  <Box style={{ flex: 1 }}>
+                    <Controller
+                      name={`extraRoutes.${i}.destinationYard`}
+                      control={form.control}
+                      render={({ field, fieldState }) => (
+                        <SelectField
+                          field={field}
+                          error={fieldState.error}
+                          label="Destination"
+                          placeholder="Destination..."
+                          disabled={stationSelectDisabled}
+                          data={rowDestData}
+                        />
+                      )}
+                    />
+                  </Box>
+                  <Button
+                    variant="subtle"
+                    color="red"
+                    size="xs"
+                    mt={24}
+                    px={6}
+                    onClick={() => removeRoute(i)}
+                  >
+                    <Trash2 size={16} />
+                  </Button>
+                </Group>
+              );
+            })}
           </Stack>
         </Box>
       )}