set TIMESTAMP_FORMAT=yyyy-mm-dd
 
for /F "tokens=* USEBACKQ" %%F in (
    `winscp.com /command "echo %%TIMESTAMP#%TIMESTAMP_FORMAT%%%" "exit"`
) do set TIMESTAMP=%%F
 
set TARGET_PATH=C:\Users\Data\%TIMESTAMP%
mkdir %TARGET_PATH%
 
"C:\Program Files (x86)\WinSCP\WinSCP.com" ^ 
  ...
  /command ^
    ...
    "lcd ""%TARGET_PATH%""" ^
    ...

"C:\Program Files (x86)\WinSCP\WinSCP.com" ^ 
  /log="C:\Users\xxxxxx\WinSCP.log" /ini=nul ^
  /command ^
    "open ftp://anonymous:anonymous%%40example.com@ftp.com.au/" ^
    "cd /xxx/xxx/xxx/xxx" ^
    "lcd ""C:\Users\Data""" ^
    "get xxxx1.nc.gz" ^
    "get xxxx2.nc.gz" ^
    "get xxxx3.nc.gz" ^
    "exit"
set WINSCP_RESULT=%ERRORLEVEL%
if %WINSCP_RESULT% equ 0 (
  echo Success
) else (
  echo Error
)
exit /b %WINSCP_RESULT%