Hi,
Are you using loading to cube directly from the datasource? It's not advisable to use upper limit unless you use cube directly. If you use DSO from the datasource, then you can use lower limit as 1 day. This will bring same delta records of yesterday and today's delta to make sure nothing is missed while loading to BW. Since we use DSO in this scenario, the repeated data will get overwritten in DSO.
Coming to your problem, you will get your delta tomorrow as you use upper limit.
Regards,
Suman