[Georgio]

Код:

@echo off
setlocal enabledelayedexpansion
(
for /f "usebackq tokens=* delims=|- " %%i in ("1.txt") do (
 echo %%i| >nul findstr /r \/.*\/20[1-9][0-9]\-[0-1][0-9]&& set x=%%i|| (
  echo %%i| >nul findstr /r 20[1-9][0-9]\-[0-1][0-9]\-[0-3][0-9]&& set y=%%i|| (
   echo !x!!y!/%%i
   )
  )
 )
)>"2.txt"
endlocal
exit /b