What happens if I change somebody’s access while they are using the app?
It takes effect within a few seconds. They are also emailed a summary of what changed and who changed it.
From the guide Team Permissions.
Who can change permissions
The account owner always can. You can also give a trusted teammate access to Team & permissions, and then they can manage the roster too — but they can never grant access they do not hold themselves. A leasing agent with team access cannot promote anybody, including themselves, to the company bank details. They also cannot change their own access at all; only the owner can.
Read the whole guide: Team Permissions