Invited to apply based on LMIA - Questions on offer letter

[RITESHNANDA]

Hi All,

My future employer filed a LMIA for my PR application in March 2016, the offer letter provided for LMIA purpose had May 1st on it.
LMIA got approved in September, and an express entry invitation was received in October.

Now my concern is if I should still attach the same offer letter that was provided on May 1st to my PR application, or shall I ask the employer to provide a new offer letter with a new date to be submitted with the express entry PR application.

If the latter, what should be the date on new offer letter?

Any help would really be appreciated.

Thanks,
Ricky