PRRA exists in order to review new risks that may present themselves to people who are facing removal from Canada. It's designed to assess risks for people who may have had a failed refugee claim and where that negative decision is old and new risks may have reasonably arisen since that ruling and should be considered.
If they can remove you fast enough, PRRA isn't required/permitted because the earlier refusal, abandonment or withdrawal of the refugee claim wasn't so long ago and it has been decided that the risk doesn't meet Canada's definition.
People have no status during that period and the idea is to remove these people within the 12 month period. If they don't remove within that timeframe, people in this situation will likely be invited to apply for PRRA.