I understand you wish to use your past data to train the predictive auto-scale model. Currently predictive autoscale does not support the experience where users can feed historical data. If you want to view the accuracy of the data, you can turn on Forecast only. Forecast only allows you to view your predicted CPU forecast without triggering the scaling action based on the prediction. You can then compare the forecast with your actual workload patterns to build confidence in the prediction models before you enable the predictive autoscale feature.
Hope this answers your question. I have passed on your feedback to the autoscale product team regarding this feature.
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