There are two parts to smartsync: Import and Provision
Import retrieves data from your MIS and imports it to realsmart, this sets up user accounts for realsmart apps such as smarthomework and smartlogin so that users can log into your WordPress smartsite.
Provision duplicates the user accounts and group memberships to G Suite for Education, pushes timetables to Google Calendar and creates and populates courses in Google Classroom

Import from MIS to realsmart - users and groups - starts at 2 am, 7 am and 10 am every day
It can take up to 2 hours for users and groups sync to complete

Provision starts at 3 am and 12 noon to give import a chance to complete
It can then take up to 6 hours for Google Provisioning to complete depending on volume. 
This means that some users have a realsmart account created before their Google account is ready to use, these can log into the website which will create the google account automatically.

 

Google Classroom sync takes place immediately after Google Users and Groups sync
Timetable to Google Calendar runs every day at 12 am (midnight)
Both can take up to 8 hours to complete depending on volume

WordPress accounts are not automatically provisioned in advance
WordPress accounts are created from the user's realsmart account info the first time a user logs in to WordPress. This saves time waiting for WordPress accounts to be provisioned and provides instant access to WordPress for all new users.