Classes are split randomly, but the results are now saved so you can pre-publish the results. When the results of a class are first calculated, the results are automatically stored to Firebase. If you come back to the class to publish the results, you'll see a "show saved results" button - pressing this will fill the results tables with the stored results, which you can then publish. If, however, you press the "calculate new results" button instead of the "show saved results", it will radomly split the class again and override the previously saved class results.

​

If you change the number of splits of a class that you already saved the results for, eg from 2 to 3, you will have to recalculate the results - the "show saved results" button won't be visible.