Configuring app protection and conditional access on mobile devices for Office365 while allowing exchange online for sync to native calendar app

I would like to use conditional access to control access to Office365 on iOS and Android using App Protection Policies and I would like to allow syncing of the work calendar to the native calendar on the mobile devices.

An APP has been set up for condition launch checking OS patch etc and a conditional access policy has been set up granting access to Office365 if APP are in place and if MFA is used.

When adding an account to a test iPhone (as an example) in settings>Calendars, Exchange Online can be selected but the message received after putting in credentials is "You can't get there from here" and "It looks like you're trying to open this resource with a client app that is not available for use with app protection policies".

Is there any way of adding an exclusion for the exchange calendar so it can be synced to the native client? There is an option to exclude default apps in the APP and that includes the iPhone calendar, but after testing I am thinking that would be allowing data for an appointment to be copied to another account in the iPhone calendar and not to the Exchange Calendar in the native calendar?