Yes. The challenges take place when it is especially cold out, during peaks periods: mornings, from 4 a.m. to 11 a.m. (4 a.m. to 6 a.m. for the preheating phase, 6 a.m. to 10 a.m. for the reduction phase and 10 a.m. to 11 a.m. for the recovery phase) and evenings, from 3 p.m. to 10 p.m. (3 p.m. to 5 p.m. for the preheating phase, 5 p.m. to 9 p.m. for the reduction phase and 9 p.m. to 10 p.m. for the recovery phase).