Removed users from distro group, but the calendar invites still remain on their calendars

I've been asked how to check and if necessary how to update their calendars, so the invite isn't on their calendar anymore.

Basically, we removed 6 users from a distro group, but the meeting invites are still on their calendars for the upcoming months.

Will they auto-update?  Can we remove the upcoming invites from the user calendars?