hi,
based on your needs for which data source your going to enhance with promotion field?
If you go with standard data source then it not possible if your data source supports delta.
if Your data source supports only full load then in such case you can use pseduo delta concept.
We need to implement abap logic at info pack level based on time and promotion changes.
if you use generic data source then check about numeric pointer delta concept.But numeric delta only accepts newly created records. it won't pulls the reocrds which are chnaged.
if your promotion field will change along with any date or time fields then thru generic data source(calday/time stamp delta concept) we can handle it.
Thanks