diff --git a/src/construction/construction.py b/src/construction/construction.py
index 484ee4e51..b5f043cde 100644
--- a/src/construction/construction.py
+++ b/src/construction/construction.py
@@ -4,6 +4,7 @@
 from typing import Callable
 
 from src.staging.validation import validate_data_with_schema
+from src.staging.staging_helpers import postcode_topup
 from src.outputs.outputs_helpers import create_period_year
 
 construction_logger = logging.getLogger(__name__)
@@ -87,6 +88,10 @@ def run_construction(
         updated_snapshot_df = create_period_year(updated_snapshot_df)
         construction_df = create_period_year(construction_df)
 
+    # Set instance=1 so longforms with status 'Form sent out' match correctly
+    form_sent_condition = (updated_snapshot_df.formtype == "0001") & (updated_snapshot_df.status == "Form sent out")
+    updated_snapshot_df.loc[form_sent_condition, "instance"] = 1
+
     # NI data has no instance but needs an instance of 1
     if is_northern_ireland:
         construction_df["instance"] = 1
@@ -115,6 +120,19 @@ def run_construction(
         {"reference": "Int64", "instance": "Int64", "period_year": "Int64"}
     )
 
+    # Long form records with a postcode in 601 use this as the postcode 
+    long_form_cond = (~updated_snapshot_df["601"].isnull())
+    updated_snapshot_df.loc[long_form_cond, "postcodes_harmonised"] = updated_snapshot_df["601"]
+
+    # Short form records with nothing in 601 use referencepostcode instead
+    short_form_cond = (updated_snapshot_df["601"].isnull()) & (~updated_snapshot_df["referencepostcode"].isnull())
+    updated_snapshot_df.loc[short_form_cond, "postcodes_harmonised"] = updated_snapshot_df["referencepostcode"]
+
+    # Top up all new postcodes so they're all eight characters exactly
+    postcode_cols = ["601", "referencepostcode", "postcodes_harmonised"]
+    for col in postcode_cols:
+        updated_snapshot_df[col] = updated_snapshot_df[col].apply(postcode_topup)
+
     construction_logger.info(f"Construction edited {construction_df.shape[0]} rows.")
 
     return updated_snapshot_df
diff --git a/src/developer_config.yaml b/src/developer_config.yaml
index a771aade6..20ed94430 100644
--- a/src/developer_config.yaml
+++ b/src/developer_config.yaml
@@ -9,7 +9,7 @@ global:
   # Staging and validation settings
   postcode_csv_check: False
   load_updated_snapshot: False # Whether to load the updated snapshots for amendments and additions
-  load_ni_data: True
+  load_ni_data: False
   load_historic_data: False
   run_construction: False
   run_ni_construction: True
@@ -37,7 +37,7 @@ global:
   output_intram_by_itl1: False
   output_intram_by_civil_defence: False
   output_intram_by_sic: False
-  output_status_filtered: False
+  output_status_filtered: True
   output_fte_total_qa: False
 years:
   current_year: 2022 # TODO: put this in the userconfig
diff --git a/src/staging/staging_helpers.py b/src/staging/staging_helpers.py
index 0cb87b58e..4d53efa52 100644
--- a/src/staging/staging_helpers.py
+++ b/src/staging/staging_helpers.py
@@ -33,8 +33,7 @@ def postcode_topup(mystr: str, target_len: int = 8) -> str:
     spaces and cuts the tail on the right.
     If there is only one part, keeps the first 8 characters and tops it up with
     spaces on the right if needed.
-    Empty input string would have zero parts and will return a string of
-    eight spaces.
+    Empty input string would have zero parts and will return an empty string.
 
     Args:
         mystr (str): Input postcode.
@@ -69,7 +68,7 @@ def postcode_topup(mystr: str, target_len: int = 8) -> str:
                 return (part1 + part2)[:target_len]
 
         else:
-            return mystr[:target_len].ljust(target_len, " ")
+            return ""
 
 
 def fix_anon_data(responses_df, config):