override staging table truncate in extract

Wondering if there is any way to override the truncation of the staging table in the extract packages? Took a look at the package and do not see way to do this. 
Thoughts? 

The default extract and load process does load source datasets from source to staging before loading to RDV, which, seems to be what you want? 

Correct.

Then the default behavior of truncating the staging table as part of the extract is fundamental to ensuring a true delta in the staging area. This in turn allows loading PSA and DV with max performance, correct row compression, and time logic. There are several options for changing the load sequences and the Data Vault load process.
                        
There are also several convenient load options that might be of interest, e.g. staged queries that allows you to decouple source to staging loads from staging to data vault loads. 
The reload to staging process that allows you to reload the staging area before loading to rdv.