diff --git a/crates/ml-backtesting/src/harness.rs b/crates/ml-backtesting/src/harness.rs
index c4c9cf6bb..0d6d80b22 100644
--- a/crates/ml-backtesting/src/harness.rs
+++ b/crates/ml-backtesting/src/harness.rs
@@ -247,7 +247,7 @@ impl BacktestHarness {
         let loader_cfg = MultiHorizonLoaderConfig {
             files,
             predecoded_dir: cfg.predecoded_dir.clone(),
-            seq_len: 1,
+            multi_resolution: ml_alpha::data::aggregation::MultiResolutionConfig::default_three_scale(),
             horizons: ml_alpha::heads::HORIZONS,
             n_max_sequences: 0,
             seed: 0,
diff --git a/crates/ml-backtesting/tests/ring3_replay.rs b/crates/ml-backtesting/tests/ring3_replay.rs
index 9cd575dd8..09c2d4181 100644
--- a/crates/ml-backtesting/tests/ring3_replay.rs
+++ b/crates/ml-backtesting/tests/ring3_replay.rs
@@ -43,7 +43,7 @@ fn try_loader() -> Option<MultiHorizonLoader> {
     let cfg = MultiHorizonLoaderConfig {
         files,
         predecoded_dir: mbp10.clone(),
-        seq_len: 1,
+        multi_resolution: ml_alpha::data::aggregation::MultiResolutionConfig::default_three_scale(),
         horizons: ml_alpha::heads::HORIZONS,
         n_max_sequences: 0,
         seed: 0xCAFE_F00D,
diff --git a/crates/ml-backtesting/tests/trainer_parity.rs b/crates/ml-backtesting/tests/trainer_parity.rs
index 4ec6680ec..66744d55e 100644
--- a/crates/ml-backtesting/tests/trainer_parity.rs
+++ b/crates/ml-backtesting/tests/trainer_parity.rs
@@ -30,7 +30,7 @@ fn try_loader(inference_only: bool) -> Option<MultiHorizonLoader> {
     let cfg = MultiHorizonLoaderConfig {
         files,
         predecoded_dir: mbp10.clone(),
-        seq_len: 1,
+        multi_resolution: ml_alpha::data::aggregation::MultiResolutionConfig::default_three_scale(),
         horizons: ml_alpha::heads::HORIZONS,
         n_max_sequences: 1,
         seed: 0xCAFEF00D,