-            #ots verify -f "$path_src" "$path_prf";
-            for url in "${calendars[@]}"; do
-                ots -l "$url" --no-default-whitelist verify -f "$path_src" "$path_prf";
-            done;
+            ### Try verify with known calendars in random order
+            while read -r url; do
+                vbm "DEBUG:Verifying with calendar:url:$url";
+                ots -l "$url" --no-default-whitelist verify -f "$path_src" "$path_prf" && break;
+            done < <(printf "%s\n" "${calendars[@]}" | shuf);