To cancel your Qt for Small Business subscription(s):
Your subscription will be canceled upon your next renewal date. When your subscription has ended, you will not be able to access Qt Creator, Qt Installer, and Maintenance Tools, and all your rights to further use Qt sources or modules will end. You must uninstall your commercial Qt. Our tools and modules are only available with an active subscription.
Note that when you wish to cancel your subscription renewal, you need to do that no less than thirty (30) days before the renewal (Appendix for Qt Development Framework, section 5.1.4).