In our online education app, we use a badging system to show progression through categories of work. These categories now need to change and the tasks within them have to be re-categorised into new categories. This requirement is enforced by external factors (specifically, a change in the national education system) which some (but not all) of our users will be familiar with.
My challenge is that some users will have completed badges in the past that are effectively 'deprecated' as part of this process. We can store a record of these achievements, but how should they be presented to users? They are ultimately of lesser value as an indicator of progress against educational attainment, so I could hide them away in an 'archive' or similar, but this might be potentially de-motivating to people who have 'lost' a lot of previously achieved badges.