Appointment scheduler with email notification

Hello,

I am in search for a plugin I can install so people can subscribe to a calendar. There is only one day the users can apply to as it is on thursday. People who subscribe for this day are willing to help a music group to do some chores to raise some money. So it is not an appointment booking plugin they have to pay for if they have made an appointment. Also another important feature is that they get notified when the day they applied for is upcoming. The best way to do that is by an email send to their own adres.

I’ve searched the internet for a plugin who can do this all, but couldn’t find any of this. The most you find are appointment bookers or event calendars. Does anyone maybe know if there is a plugin which can help me with this all?

Many thanks!! ??