Locksider and Locksider+ for Windows Phone have both been updated. We've been informed by the developer, Liquid Daffodil that both releases fix an issue relating to consistent lock screen updates, or rather lack of. The team relied too heavily on consistent patterns in the background agents, which often caused scheduled updates to be skipped. What has been put in place is a more reliable update pattern.
So how does one get on top of said issue? Simply update either version of Locksider and re-establish the set update schedules. This is a simple process and only requires each user to hop into the app settings and select a schedule. The updates should then be consistent throughout the course of each day.
Liquid Daffodil also asks those who use Locksider to update any reviews that noted the problem and email them with thoughts on how the update has sorted the issue. You can download Locksider and Locksider+ (for $0.99 and $1.49 respectively) from the Windows Phone Store.