windows batch rename file with delay

@echo off
echo Rename Tool started:
date /t
time /t
echo .
echo .
:start

if exist test1.txt (
  REM  do nothing!
) else (
  if exist test2.txt (
    echo .
    date /t 
    time /t
    echo "rename test1.txt -> test2.txt..."
    ren test1.txt test2.txt
  )
)

wait 30
goto start