I did some research on optimal trial lengths. Originally I thought we'd offer a 14 day trial. After some heavy reading, I decided that 14 days is way too long given this is a consumer product and it's priced fairly low. I changed the trial length to 7 days, thought about it some more, and changed it to 5 days.
That means that some of the 7 day trials should start expiring today, followed by the 5 day trials tomorrow. The 14 day trials should start to expire on 20 January.