You can give those members an access level of "No Access" in the BambooHR platform. Please note that if those members have any other additional access levels they will still get provisioned.
The other way is to segment your employees by using a specific field and values.
Go to the integrations Dashboard in Reward Manager and on the "Mapping" step of your configuration, at the bottom of the page, you will have the option to enable this.
You can set a specific value and we will only create accounts for employees with this value.
Whenever a member doesn't have the needed value set in the segmentation, they will get revoked or an account won't be created until you add it to their BambooHR account.
This works for probational periods as well so whenever the members pass the probation period, you just need to change the values that we're using on their account in Bamboo and their account will be created.