diff --git a/gso/workflows/iptrunk/migrate_iptrunk.py b/gso/workflows/iptrunk/migrate_iptrunk.py
index 6f99015c8bc3518d616dc919927b2ca673e3bd38..11294d9e2c50fb29b55eb99370162fb6d12c39aa 100644
--- a/gso/workflows/iptrunk/migrate_iptrunk.py
+++ b/gso/workflows/iptrunk/migrate_iptrunk.py
@@ -658,7 +658,7 @@ def update_subscription_model(
     subscription.iptrunk.iptrunk_sides[replace_index].iptrunk_side_ae_members.clear()
     #  And update the list to only include the new member interfaces
     for member in new_lag_member_interfaces:
-        subscription.iptrunk.iptrunk_sides[0].iptrunk_side_ae_members.append(
+        subscription.iptrunk.iptrunk_sides[replace_index].iptrunk_side_ae_members.append(
             IptrunkInterfaceBlock.new(subscription_id=uuid4(), **member),
         )