Bulk unsubscribe more than 25 at a time?

Hi there. I made an oversight when migrating to a new web host and the setting to “automatically subscribe registered users to new categories” was enabled.

I now have ~1,500 registered users who are subscribed to two new categories, and they shouldn’t be.

There is a handy function to bulk unsubscribe registered users (described here) and it works well, but can only work on 25 users at a time (the maximum number shown in a page of users).

Is there a way to show a longer list so I could unsub 50, or 100, or 200 at a time?

Thanks!