diff --git a/scripts/deploy.sh b/scripts/deploy.sh
index 343ba17..0c2fadf 100755
--- a/scripts/deploy.sh
+++ b/scripts/deploy.sh
@@ -249,9 +249,10 @@ chmod 755 /etc/init.d/mk8-guard
 
 # Post-deploy verification: API must answer within ~60s (deadline-capped so
 # hung connections cannot stretch the window) or we roll back.
-DEADLINE=\$((SECONDS + 60))
+T0=\$(date +%s)
+DEADLINE=\$((\$T0 + 60))
 HEALTH_OK=''
-while [ \$SECONDS -lt \$DEADLINE ]; do
+while [ \$(date +%s) -lt \$DEADLINE ]; do
     if curl -fsS -m 3 http://127.0.0.1:8080/ >/dev/null 2>&1; then
         HEALTH_OK=1
         break