diff --git a/h2mm b/h2mm
index ceadec3..96ddbca 100755
--- a/h2mm
+++ b/h2mm
@@ -377,7 +377,7 @@ EOF
 function check_for_updates() {
 	if [[ -f "$LAST_CHECKED_UPDATE_FILE" ]]; then
 		last_update=$(cat "$LAST_CHECKED_UPDATE_FILE")
-		if [[ "$(date +%s)" -lt "$(date +%s -d "$last_update + 1 hour")" ]]; then
+		if [[ "$(date +%s)" -lt $(("$(date +%s -d "$last_update")" + 3600)) ]]; then
 			return
 		fi
 	else