I believe it was because it was set as a priority in order to address that class of applications, and hence resources were focused on that. We see that often that, when the government sets immigration levels, they are divided by the different types of classes, whether they be humanitarian, economic or family reunification. However, at times, priorities come up. For example, in the past we would have seen that, when Syrian refugees were being accepted into the country, there was a priority. Resources get rerouted, and applications get processed more quickly. That means there is a domino effect for those sitting in the inventory.
That's why it's really important for the department to understand the capacity of their offices and to be able to route applications in a better way. Right now, it is definitely resulting in differential outcomes either across programs or across the country for citizenship.