diff --git a/freqtrade/data/history/history_utils.py b/freqtrade/data/history/history_utils.py
index 5cdcd7276..4f3f75a87 100644
--- a/freqtrade/data/history/history_utils.py
+++ b/freqtrade/data/history/history_utils.py
@@ -260,7 +260,9 @@ def _download_trades_history(exchange: Exchange,
     """
     try:
 
-        since = timerange.startts * 1000 if timerange and timerange.starttype == 'date' else None
+        since = timerange.startts * 1000 if \
+            (timerange and timerange.starttype == 'date') else int(arrow.utcnow().shift(
+                days=-30).float_timestamp) * 1000
 
         trades = data_handler.trades_load(pair)
 
@@ -282,9 +284,7 @@ def _download_trades_history(exchange: Exchange,
 
         # Default since_ms to 30 days if nothing is given
         new_trades = exchange.get_historic_trades(pair=pair,
-                                                  since=since if since else
-                                                  int(arrow.utcnow().shift(
-                                                      days=-30).float_timestamp) * 1000,
+                                                  since=since,
                                                   from_id=from_id,
                                                   )
         trades.extend(new_trades[1])
diff --git a/tests/conftest.py b/tests/conftest.py
index 517a11b47..a4beeec33 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -1233,6 +1233,7 @@ def trades_history():
             [1565798399862, '126181332', None, 'sell', 0.019626, 0.011, 0.00021588599999999999],
             [1565798399872, '126181333', None, 'sell', 0.019626, 0.011, 0.00021588599999999999]]
 
+
 @pytest.fixture(scope="function")
 def fetch_trades_result():
     return [{'info': {'a': 126181329,
diff --git a/tests/data/test_converter.py b/tests/data/test_converter.py
index 463700d0c..4a580366f 100644
--- a/tests/data/test_converter.py
+++ b/tests/data/test_converter.py
@@ -218,33 +218,37 @@ def test_trades_dict_to_list(fetch_trades_result):
         assert t[6] == fetch_trades_result[i]['cost']
 
 
-
 def test_convert_trades_format(mocker, default_conf, testdatadir):
-    file = testdatadir / "XRP_ETH-trades.json.gz"
-    file_new = testdatadir / "XRP_ETH-trades.json"
-    _backup_file(file, copy_file=True)
-    default_conf['datadir'] = testdatadir
+    files = [{'old': testdatadir / "XRP_ETH-trades.json.gz",
+              'new': testdatadir / "XRP_ETH-trades.json"},
+             {'old': testdatadir / "XRP_OLD-trades.json.gz",
+              'new': testdatadir / "XRP_OLD-trades.json"},
+             ]
+    for file in files:
+        _backup_file(file['old'], copy_file=True)
+        assert not file['new'].exists()
 
-    assert not file_new.exists()
+    default_conf['datadir'] = testdatadir
 
     convert_trades_format(default_conf, convert_from='jsongz',
                           convert_to='json', erase=False)
 
-    assert file_new.exists()
-    assert file.exists()
+    for file in files:
+        assert file['new'].exists()
+        assert file['old'].exists()
 
-    # Remove original file
-    file.unlink()
+        # Remove original file
+        file['old'].unlink()
     # Convert back
     convert_trades_format(default_conf, convert_from='json',
                           convert_to='jsongz', erase=True)
+    for file in files:
+        assert file['old'].exists()
+        assert not file['new'].exists()
 
-    assert file.exists()
-    assert not file_new.exists()
-
-    _clean_test_file(file)
-    if file_new.exists():
-        file_new.unlink()
+        _clean_test_file(file['old'])
+        if file['new'].exists():
+            file['new'].unlink()
 
 
 def test_convert_ohlcv_format(mocker, default_conf, testdatadir):