There were some things apprentices weren't privy to and that much was certain as Sir Gunnar and Sven went off with the mages to investigate the situation in the forest much more thoroughly. When the knights returned, there was nothing to share with the apprentices.
From that point forward, Leif, Irene, and Felix were told not to tell the other apprentices about what they saw. The situation of footprints in the mud and snow going towards the Duke's Tower was too strange for them to tell the others. It gave the place a bit of a mistrustful edge, and Irene felt unstable for the first time in a long time since she had been there.
What the others referred to as false spring happened in the following week after what they found in the forest. Everyone near the Duke's Tower fell asleep to a heavy frost having settled in and woke up to snow pouring over the earth and recovering what had been melted. The days that felt so warm and invigorating were chased away.