You may have been billed a little early or later than expected because you are not in the same time zone as our billing system. We bill out of UTC, so if you start a subscription late in your day, it is early. The result can be a perception of being billed a day before compared to the confirmation email. It is always a good idea to make account changes at least 24 hours ahead of the stated bill date.
Billed at the end of your free trial?
You may be billed for a STARZ subscription at the end of your free trial period if you have not canceled within 24 hours of the trial ends.