When a Verkada camera detects tampering, it immediately begins a cloud backup process to maximize the probability that you'll get video of the event. The camera uploads the live video, thumbnails, and recorded video from the last minute to the cloud when tampering is detected. This is configured by default regardless of your settings.
If you'd also like to be alerted of tampering you can enable Tamper Detection Alerts:
Select Live on the left-hand bar
Next to Cameras, select the bell icon
Choose SMS, Email, or both next to Tamper