Yes! However, that app will count towards your limit of unlocked apps until the end of your billing cycle. If you scheduled an app for removal by accident, you can always cancel the removal.
For example, let's say you are on a "Launch" plan and are currently unlocking data for 10 apps, which is your limit. You want to remove an app from your unlocked apps. It's fine, but you will not be able to unlock any more apps (unless you upgrade) until the end of your billing cycle.
Careful! If you remove an app from unlocked apps, you may be removing an app from one of your team mates' watchlist! So be sure to always ask your teammates before removing apps from the "unlocks" list.