StreamSpot billing cycles are set to 1-month from the date you activated your account by default. For example, if you activated your plan on May 14th, your next invoice will be generated on June 14th.
For reference, the days remaining in your current billing cycle are displayed in your "Plan Usage Summary" on the MyStreamSpot dashboard:
Bi-annual, and annual invoicing is available, for more information check out this article.
To learn more about how StreamSpot Activation and Payments work, see the links to the other Knowledgebase articles below: