Yup what he said. All your units use a template that you can change and modify. When you add, or change anything with that template any units made with it willIf you are asking because of the latest stream, they had to do that for their armored divisions because, rather than merely updating their division template (which would change deployed forces automatically), they created an entirely new template. This meant that all the old armored divisions had to be manually changed over to the new template.