If you have not sent it back to Endevor then the old version will still be there.
If you mean that the program has never been on Endevor then...were you changing the original? If so, WHY? (And how were you authorised to change it?). If you are lucky there may be a backup of the PDS that the member is in. If you are unlucky then there may still be a copy of the previous compile. If you are extremely unlucky...start looking for a new job.
And do not ask about backups - they are site specific so speak to colleagues in your department/storage guys.
The problem I have is that people can explain things quickly but I can only comprehend slowly.