Have you tried removing the subscription filter to see if it fires for that day-2? Even if it just calls a test WF that just logs something for example.
I am not sure about the built-in RAs but for custom ones the display name and the name are separate fields. I wonder if the actual name of the "Resize Boot Disk" is something like ResizeBootDisk instead? If you can get the sub to fire in general, then maybe you can inspect the payload to confirm the name of the action?