Uscreen is one of the few platforms that gives you full access to your users. You can quickly export users in a CSV file and have it available for download at any time.
Navigate to the People tab, and under the second People tab, click Export CSV. It should download right away unless you've got a massive user list. A new tab will open if that's the case, and it will need to remain open while it prepares the CSV file.
If you would like a more specific report, you can filter it by Date and Subscription Status to then export it. For example, if you want to only export those users who had been active during May, you would simply select the dates and status and then click on Export CSV.