Utilize mailchimp’s recent change to allow single opt-in

Mailchimp recently made changes (starting 10/31/2017) to allow single opt-ins. I’ve done some testing on my site, which uses this plugin, and it’s still using the double opt-in.

Is there a way to use this plugin with single opt-in?

I like how this plugin works with my theme’s styling, and don’t want to switch to something else. But single opt-in is more important to me than that, so I’ll need to find an alternative if this can’t be forced to do single opt-in.

Thanks!