diff --git a/data_subscriber/asf_cslc_download.py b/data_subscriber/asf_cslc_download.py
index 5c4495e7..8974b789 100644
--- a/data_subscriber/asf_cslc_download.py
+++ b/data_subscriber/asf_cslc_download.py
@@ -288,19 +288,30 @@ def get_downloads(self, args, es_conn):
 
         all_downloads = []
 
-        # Download CSLC granules
-        downloads = es_conn.get_download_granule_revision(batch_ids[-1])
-        logger.info(f"Got {len(downloads)=} cslc granules downloads for batch_id={batch_ids[-1]}")
-        assert len(downloads) > 0, f"No downloads found for batch_id={batch_ids[-1]}!"
-        all_downloads.extend(downloads)
-
-        # Download K-CSLC granules
-        for batch_id in batch_ids[:-1]:
-            downloads = k_es_conn.get_download_granule_revision(batch_id)
-            logger.info(f"Got {len(downloads)=} k cslc downloads for {batch_id=}")
-            assert len(downloads) > 0, f"No downloads found for batch_id={batch_id}!"
+        # Historical mode stores all granules in normal cslc_catalog
+        if "proc_mode" in args and args.proc_mode == "historical":
+            logger.info("Downloading cslc files for historical mode")
+            for batch_id in batch_ids:
+                downloads = es_conn.get_download_granule_revision(batch_id)
+                logger.info(f"Got {len(downloads)=} cslc downloads for {batch_id=}")
+                assert len(downloads) > 0, f"No downloads found for batch_id={batch_id}!"
+                all_downloads.extend(downloads)
+
+        # Forward and reprocessing modes store all granules in k_cslc_catalog
+        else:
+            logger.info("Downloading cslc files for forward/reprocessing mode")
+            downloads = es_conn.get_download_granule_revision(batch_ids[-1])
+            logger.info(f"Got {len(downloads)=} cslc granules downloads for batch_id={batch_ids[-1]}")
+            assert len(downloads) > 0, f"No downloads found for batch_id={batch_ids[-1]}!"
             all_downloads.extend(downloads)
 
+            # Download K-CSLC granules
+            for batch_id in batch_ids[:-1]:
+                downloads = k_es_conn.get_download_granule_revision(batch_id)
+                logger.info(f"Got {len(downloads)=} k cslc downloads for {batch_id=}")
+                assert len(downloads) > 0, f"No downloads found for batch_id={batch_id}!"
+                all_downloads.extend(downloads)
+
         return all_downloads
 
     def query_cslc_static_files_for_cslc_batch(self, cslc_files, args, token, job_id, settings):
diff --git a/data_subscriber/cslc/cslc_query.py b/data_subscriber/cslc/cslc_query.py
index c31e4e29..7292c3e9 100644
--- a/data_subscriber/cslc/cslc_query.py
+++ b/data_subscriber/cslc/cslc_query.py
@@ -437,7 +437,6 @@ def query_cmr(self, args, token, cmr, settings, timerange, now):
     def create_download_job_params(self, query_timerange, chunk_batch_ids):
         '''Same as base class except inject batch_ids for k granules'''
 
-        assert len(chunk_batch_ids) == 1
         chunk_batch_ids.extend(list(self.k_batch_ids[chunk_batch_ids[0]]))
         return super().create_download_job_params(query_timerange, chunk_batch_ids)
 
@@ -478,16 +477,25 @@ def get_download_chunks(self, batch_id_to_urls_map):
         '''For CSLC chunks we must group them by the batch_id that were determined at the time of triggering'''
 
         chunk_map = defaultdict(list)
+        if len(list(batch_id_to_urls_map)) == 0:
+            return chunk_map.values()
+
+        frame_id, _ = split_download_batch_id(list(batch_id_to_urls_map)[0])
+
         for batch_chunk in batch_id_to_urls_map.items():
-            chunk_map[batch_chunk[0]].append(batch_chunk) # We don't actually care about the URLs, we only care about the batch_id
-
-            '''indices = self.download_batch_ids[batch_chunk[0]]
-            for index in indices:
-                chunk_map[index].append(batch_chunk)
-                if (len(chunk_map[index]) > self.args.k):
-                    logger.error([chunk for chunk, data in chunk_map[index]])
-                    err_str = f"Number of download batches {len(chunk_map[index])} for frame {index} is greater than K {self.args.k}."
-                    raise AssertionError(err_str)'''
+
+            # Chunking is done differently between historical and forward/reprocessing
+            if self.proc_mode == "historical":
+                chunk_map[frame_id].append(batch_chunk)
+            else:
+                chunk_map[batch_chunk[0]].append(
+                    batch_chunk)  # We don't actually care about the URLs, we only care about the batch_id
+
+        if self.proc_mode == "historical":
+            if (len(chunk_map[frame_id]) != self.args.k):
+                logger.error([chunk for chunk, data in chunk_map[frame_id]])
+                err_str = f"Number of download batches {len(chunk_map[frame_id])} for frame {frame_id} does not equal K {self.args.k}."
+                raise AssertionError(err_str)
 
         return chunk_map.values()