Develop a new model exclusively with data from the newly added services and use an ensemble method to combine predictions from both the old and new models.

Retrain the existing model using only the most recent week's customer feedback data to quickly adapt to changes in customer satisfaction trends.

Update the existing model by incorporating feedback data from the new services and establish a scheduled retraining and evaluation pipeline to ensure the model remains accurate over time.

Defer any updates to the model, assuming its current accuracy and generalization capability will suffice for the new services without additional retraining.

Implement a continuous integration/continuous deployment (CI/CD) pipeline for the model that automatically retrains and deploys the model based on new data, while also setting up monitoring for model performance and data drift.