diff --git a/freqtrade/optimize/hyperopt.py b/freqtrade/optimize/hyperopt.py
index 4c8613a7a..3becf857f 100644
--- a/freqtrade/optimize/hyperopt.py
+++ b/freqtrade/optimize/hyperopt.py
@@ -421,8 +421,9 @@ class Hyperopt:
         preprocessed = self.backtesting.strategy.advise_all_indicators(data)
 
         # Trim startup period from analyzed dataframe to get correct dates for output.
-        processed = trim_dataframes(preprocessed, self.timerange, self.backtesting.required_startup)
-        self.min_date, self.max_date = get_timerange(processed)
+        trimmed = trim_dataframes(preprocessed, self.timerange, self.backtesting.required_startup)
+        self.min_date, self.max_date = get_timerange(trimmed)
+        # Real trimming will happen as part of backtesting.
         return preprocessed
 
     def prepare_hyperopt_data(self) -> None: