Office 365 Licening Requirements in an ADFS Single Sign-On Scenario

Good Evening All,

Hoping to get some clarification around a licensing scenario that a colleague and I are facing.  Our client is hoping to license users for access to Office 365 using a Kiosk or K1 license but are configured for Federated Single Sign-On using ADFS.  If we are required to create the user account On Premise for DirSync purposes; will this user require a client CAL for sign-in even if the only resource they're using is Office 365?

Cheers,

Hayden