diff --git a/cats/__init__.py b/cats/__init__.py
index ad1ad04..b0af2ca 100644
--- a/cats/__init__.py
+++ b/cats/__init__.py
@@ -118,7 +118,7 @@ def main(arguments=None):
     # Find best possible average carbon intensity, along
     # with corresponding job start time.
     now_avg, best_avg = get_avg_estimates(
-        CI_forecast, method="windowed", duration=duration
+        CI_forecast, duration=duration
     )
     sys.stderr.write(str(best_avg) + "\n")
 
diff --git a/cats/optimise_starttime.py b/cats/optimise_starttime.py
index 67aebee..6fe1155 100644
--- a/cats/optimise_starttime.py
+++ b/cats/optimise_starttime.py
@@ -2,7 +2,7 @@
 from .forecast import WindowedForecast
 
 
-def get_avg_estimates(data, method="simple", duration=None):
+def get_avg_estimates(data, duration=None):
     """
     Get lowest carbon intensity in data depending on user method
     return dict of timestamp and carbon intensity
@@ -17,22 +17,12 @@ def get_avg_estimates(data, method="simple", duration=None):
     #         "Windowed method timespan cannot be greater than the cached timespan"
     #     )
 
-    METHODS = ["simple", "windowed"]
-    if method not in METHODS:
-        raise ValueError(f"Invalid Carbon Intensity Method. Must be one of {METHODS}")
-
-    if method == "simple":
-        #  Return element with smallest 2nd value
-        #  if multiple elements have the same value, return the first
-        return min(data)
-
-    if method == "windowed":
-        # get length of interval between timestamps
-        interval = (
-            data[1].datetime - data[0].datetime
-        ).total_seconds() / 60
-        wf = WindowedForecast(
-            data=data,
-            window_size=ceil(duration / interval)
-        )
-        return wf[0], min(wf)
+    # get length of interval between timestamps
+    interval = (
+        data[1].datetime - data[0].datetime
+    ).total_seconds() / 60
+    wf = WindowedForecast(
+        data=data,
+        window_size=ceil(duration / interval)
+    )
+    return wf[0], min(wf)
diff --git a/tests/test_timeseries_conversion.py b/tests/test_timeseries_conversion.py
deleted file mode 100644
index 2c87491..0000000
--- a/tests/test_timeseries_conversion.py
+++ /dev/null
@@ -1,33 +0,0 @@
-from pathlib import Path
-from datetime import datetime
-import csv
-
-from cats.optimise_starttime import get_avg_estimates
-from cats.forecast import CarbonIntensityPointEstimate
-
-
-TEST_DATA = Path(__file__).parent / "carbon_intensity_24h.csv"
-
-
-def test_stub():
-    pass
-
-
-def test_timeseries_conversion():
-    with open(TEST_DATA, "r") as f:
-        csvfile = csv.reader(f, delimiter=",")
-        next(csvfile)  # Skip header line
-        forecast_data = [
-            CarbonIntensityPointEstimate(
-                datetime=datetime.fromisoformat(datestr[:-1]),
-                value=float(intensity_value),
-            )
-            for datestr, _, _, intensity_value in csvfile
-        ]
-    result = get_avg_estimates(
-        forecast_data, method="simple", duration=None
-    )
-    assert result == CarbonIntensityPointEstimate(
-        datetime=datetime(2023, 5, 5, 14, 0),
-        value=5.0,
-    )