When running the jumpstart command,and if there is already magnolia.zip - no bundle artifact downloaded.
Fair enough.
However, in consequence neither the -e nor -m option have any influence.
It just takes the version which was chosen the last time when it had to download.

The "easiest" fix seems to be to delete the zip file after successful installation

Implementation
With the new tomcat & webapp feature - (https://jira.magnolia-cms.com/browse/NPMCLI-120) the directory starts to get cluttered with the downloads.

• The webapp and tomcat are downloaded to a new directory "downloads".
• The files are not renamed to generic names but keep their full names.
• When user runs jumpstart - if the exact requested webapp is present in the downloads directory, then it is used. If they had requested a different webapp, then that webapp is downloaded and extracted. This ensures that the user always gets the exact webapp that they had requested.