Hello Juan Carlos,
I would guess that you are not using ASE for SAP applications, as on that environment we *should* have the "trunc log on chkpt" disabled, and a dump with truncate_only *is not* recommended as it break the recoverability of the environment.
So I'll move the discussion to the SAP ASE for custom applications 
Regarding the question: is the batch just doing updates of some bulk inserts?
Can we check the sp_dboptions of the concerned database ?
Just to keep in mind that the "trunc og on chkpt" will remote *committed transactions* from the transaction log.
Best regards,
Victoria.