The way I would approach this would be to use a startup form. (I have one, but it doesn't do the kick-out.) It does some logging for me so I can track usage. My users have to click a button on the form to get past it.
When they click the button, the form doesn't go away, it just minimizes and goes non-visible. But it has a timer in it. Once every so often, the timer wakes up to check the current time of day and the first record in my "DB Events" table. This table has a descriptive field and some time fields. If the current time is between the start and end time for an event, the user gets a message box warning of the event. Right now I am on the honor system, which works in my shop. But they know I could do much worse things to them if I needed to.
I suppose you could adapt this code to include an option to kick folks out. I would do it by checking the user ID or group ID. If they are not supposed to be there, I would open an OKOnly box, letting them click "OK" on the box that says "You are about to be kicked out." Then immediately do a DoCmd.Quit on them.