Using the following as an example. It is possible to use FlexReports to see a specific instance size changes.
If you build a FlexReport for this specific Instance ID “i-032f9edbd0fbbf066”, you can see the Instance size change on Feb 1, where the price drops.
Table view of the same data:
Below is a screen shot of the setup for this particular FlexReport. This can be configured in the UI or API.