First you will log into the mydata portal 

From the dashboard follow the steps below:

Multiple System:

1)Scroll down to Backup Summary

2)Click Manage next to the system you wish to Disable Backup During Selected Hours. (Note: System must have status Connected)

3)Follow steps for Single System below moving forward. 

Single System:

1)Scroll down to Disable Backup During Selected Hours

3)Click hours you wish the backups to disable during (Note: You can use Block Work Hours to disable backup during the default 9am-5pm Mon-Fri)

4)Once done selection click Save when done selecting hours you wish to disable the backup during.