diff -ur b/atd.c a/atd.c
--- b/atd.c	2022-02-22 15:55:28.745663105 +0100
+++ a/atd.c	2022-02-22 16:07:26.416578085 +0100
@@ -722,12 +722,18 @@
 	/* Is the file already locked?
 	 */
 	if (buf.st_nlink > 1) {
+	    if (run_time < buf.st_mtime)
+		run_time = buf.st_mtime;
 	    if (run_time + CHECK_INTERVAL <= now) {
 
 		/* Something went wrong the last time this was executed.
 		 * Let's remove the lockfile and reschedule.
+		 * We also change the timestamp to avoid rerunning the job more
+		 * than once every CHECK_INTERVAL.
 		 */
 		strncpy(lock_name, dirent->d_name, sizeof(lock_name));
+		if (utime(lock_name, 0) < 0)
+			syslog(LOG_ERR, "utime couldn't be set for lock file %s\n", lock_name);
         lock_name[sizeof(lock_name)-1] = '\0';
 		lock_name[0] = '=';
 		unlink(lock_name);