gistfile1.txt

@echo off
setlocal EnableExtensions EnableDelayedExpansion

:: Use WMIC to retrieve date and time in a consistent format
for /f "tokens=2 delims==," %%x in ('wmic os get localdatetime /value') do set datetime=%%x

:: Extract the date in YYYYMMDD format
set "year=!datetime:~0,4!"
set "month=!datetime:~4,2!"
set "day=!datetime:~6,2!"

:: Rename files containing 'FDD' or 'MP'
for %%i in (*FDD*.*) do ren "%%i" "8851 FDD !year!!month!!day!.xlsx"
for %%i in (*MP*.*) do ren "%%i" "8851 MP !year!!month!!day!.xlsx"