How does one backout events and jobs during maintenance slots?

Management and data collection activity can be suspended by imposing a blackout. Look at these examples:

agentctl start blackout		# Blackout the entrire agent
agentctl stop blackout		# Resume normal monitoring and management

agentctl start blackout ORCL		# Blackout database ORCL
agentctl stop blackout ORCL		# Resume normal monitoring and management

agentctl start blackout -s jobs -d 00:20		# Blackout jobs for 20 minutes