Exchange Online Advanced Threat Protection Should Be Included
Exchange Online Protection is a joke and does little to nothing to protect end users from malware infected files. MS touts Exchange Online as secure, but really it's not -- unless you pay more on top of what you're already paying for supposed security.
James Read commented
With the lack of malware protection in the base Exchange Online Protection product it would make sense not to charge an additional fee for Exchange Online Advanced Threat Protection.