diff --git a/infra/postfix/pw-mta-warmup.sh b/infra/postfix/pw-mta-warmup.sh
index a667ffd..0245652 100755
--- a/infra/postfix/pw-mta-warmup.sh
+++ b/infra/postfix/pw-mta-warmup.sh
@@ -24,8 +24,10 @@ MAINCF=/etc/postfix/main.cf
 POSTCONF=/usr/sbin/postconf
 POSTFIX=/usr/sbin/postfix
 
-# Rotation transports (.91-.109). .90 is Yahoo-dedicated, not in rotation.
-ALL=(out02 out03 out04 out05 out06 out07 out08 out09 out10 out11 \
+# Rotation transports. .90 is Yahoo-dedicated, not in rotation. out02/03/04
+# (.91/.92/.93) were reputation-torched by the May 30-31 over-volume blast and
+# are retired. Warmup starts at fresh out05 (.94).
+ALL=(out05 out06 out07 out08 out09 out10 out11 \
      out12 out13 out14 out15 out16 out17 out18 out19 out20)
 
 if [ "${1:-}" = "--start" ]; then
@@ -42,7 +44,10 @@ elif [ "$DAYS" -le 7 ];  then N=5
 elif [ "$DAYS" -le 11 ]; then N=8
 elif [ "$DAYS" -le 17 ]; then N=12
 elif [ "$DAYS" -le 24 ]; then N=16
-else N=19; fi
+else N=16; fi
+
+# Safety: never request more transports than exist in ALL.
+if [ "$N" -gt "${#ALL[@]}" ]; then N=${#ALL[@]}; fi
 
 POOL=""
 for ((i=0; i<N; i++)); do POOL="${POOL}${ALL[$i]}:,"; done