diff --git a/inst/testhubs/flusight/hub-config/validations.yml b/inst/testhubs/flusight/hub-config/validations.yml
index 7727f434..62cdf578 100644
--- a/inst/testhubs/flusight/hub-config/validations.yml
+++ b/inst/testhubs/flusight/hub-config/validations.yml
@@ -6,5 +6,3 @@ default:
         args:
           t0_colname: "forecast_date"
           t1_colname: "target_end_date"
-          horizon_colname: "horizon"
-          timediff: !expr lubridate::weeks()