diff --git a/ci-scripts/conf_files/gnb.sa.band78.24prb.rfsim.conf b/ci-scripts/conf_files/gnb.sa.band78.24prb.rfsim.conf
index 4a3d2852c4..afe40c733c 100644
--- a/ci-scripts/conf_files/gnb.sa.band78.24prb.rfsim.conf
+++ b/ci-scripts/conf_files/gnb.sa.band78.24prb.rfsim.conf
@@ -196,6 +196,7 @@ RUs = (
   att_tx         = 0
   att_rx         = 0;
   bands          = [78];
+  sl_ahead=3;
   max_pdschReferenceSignalPower = -27;
   max_rxgain                    = 114;
   sf_extension                  = 0;