Need to exclude post title

I have a CPT called “Updates”, I used it for twitter like kind of short updates. However I do not want the slug to be too long, so I thought I could use this plugin to modify the permalink to just show the post ID, eg domain.com/updates/1234

Under the Permastructures tab, this is how I set it for the CPT:
updates/%post_id%

However, the generated slugs now include both the ID and the slug. What am I missing?
domain.com/updates/1234/the-long-title-here