Model Initialization Strategy in RLHF

A team is developing a large language model aligned with human preferences using a reinforcement learning approach. Arrange the following key phases of their training pipeline into the correct chronological order.

An AI development team is in the final stage of a three-part alignment process for their language model. They observe that the model's outputs are becoming increasingly nonsensical, even though the reward scores assigned during this final stage are consistently high. The team has already confirmed that the initial models were set up correctly and that the dataset of human preferences used in the second stage is high-quality. Based on this information, what is the most probable cause of the model