You can view operation logs in the last 30 days on the logs page in the new Anti-DDoS Pro console.

Note Operation logs only record important operations in the last 30 days.
Recorded operation Supported
Change the IP of ECS instances Yes
Deactivate black holes Yes
Block or unblock traffic Yes
Change the scrubbing mode of layer 4 traffic Yes
Change the HTTP flood protection mode Yes
Change the burstable bandwidth Yes