>>6にひと加えしただけだよん

--- BDAV.TXT ---
for /f %%i in ( 'bnlba e' ) do set BDAV_BNLBA=%%i
echo %BDAV_BNLBA% > BDAV_LBA.TXT
copy BDAV_PRE.TXT+BDAV_LBA.TXT > BDAV.TXT
BackupBDAVforV1.cmd <BDAV.TXT

--- BDAV_PRE.TXT ---
e
d:\