Having the extra query really depends on what you’re doing.
You say that weeks is a post type. I would probably look at using the template file “archive-weeks.php” https://developer.wordpress.org/themes/basics/template-hierarchy/ and using a pre_get_post filter to modify the main WP query https://codex.wordpress.org/Plugin_API/Action_Reference/pre_get_posts. Use the main query to my advantage rather than ignore it.
But like I said, that depends on exactly why you’re doing it the way your doing it. I don’t know all the details.
