I understand that this study plan is time-boxed, but from a UX perspective I am not sure why a learner's progress needs to reset. It's kind of frustrating if you don't finish the problems within the 14 days (plus some buffer), that all progress resets and you have to completely start over and wait as the problems trickle out every 24 hours, especially since the problem list is completely static. If it was a randomized list of problems each time you began the study plan, then it might make more sense that it resets each time you begin. Is there a way the learner could select which option works best for them?