Hi,
thanks for your post.
Yes, the Auto Import Extension will take care of changed sizes automatically, as it just replaces the current version of the table with the version from the imported file/URL.
So, if a table has 20 rows now, but the new version in the file/URL has 25, the imported table will have all 25, and vice versa.
Messing around with extra empty lines is therefore not possible or necessary.
Regards,
Tobias