Dataset Incremental Refresh - Data Type changed - import mode from Tabular

Hi Everyone!

Context: we are refreshing a dataset by importing the data from a SSAS Tabular model OnPrem
Idea is now to activate the Incremental Refresh of that dataset. 

The concern we have is that all Date/int type fields are imported as string! even if they are set correctly in the Tabular Model

The query becomes non foldable as soon as we cast the ReferenceDate from string to date in powerquery ... 

Any idea by type conversion occurs when importing data from a Tabular?

Thanks for your answer