diff --git a/services/domain/Big.Domain/Registration.cs b/services/domain/Big.Domain/Registration.cs
index ea19202..89f5994 100644
--- a/services/domain/Big.Domain/Registration.cs
+++ b/services/domain/Big.Domain/Registration.cs
@@ -115,9 +115,9 @@ public sealed class Registration
     // per-catalogus, promote it to policy passed in from the beheer config (S-15).
     public static readonly TimeSpan HerregistratieGeldigheid = TimeSpan.FromDays(365 * 5);
 
-    /// <summary>How long before the deadline the herregistratie reminder is sent (BIG: ~16 weeks).</summary>
-    // ponytail: fixed 16-week lead time — calibration knob; same promotion path as HerregistratieGeldigheid.
-    public static readonly TimeSpan Herinneringstermijn = TimeSpan.FromDays(16 * 7);
+    /// <summary>How long before the deadline the herregistratie reminder is sent (S-17: 90 days).</summary>
+    // ponytail: fixed 90-day lead time — calibration knob; same promotion path as HerregistratieGeldigheid.
+    public static readonly TimeSpan Herinneringstermijn = TimeSpan.FromDays(90);
 
     /// <summary>When the registration was entered in the register, once approved; the start of its
     /// herregistratie clock. Null until it is <see cref="RegistrationStatus.Ingeschreven"/>.</summary>