Flexible Hourly Self-Scheduling for Open Volunteer Hours

Most of our program volunteer opportunities are scheduled per a volunteer's availability during our open 'business' hours (9a-5p), not a set 2-3 hour shift time. It would be extremely helpful to have a self-scheduling option where we can input start/end time for a day and # of volunteer parameters but then volunteers can select/create their own hourly shift within those parameters. (And please advise if this functionality is there that I'm not aware of. We use General Check-In but still need to utilize scheduling.)

As an example, volunteers can help with our facilities or be on call for childcare or translation assistance anytime during our daytime hours. Currently, we have to create a separate shift for each hour of the day (9a-5p), each day of the week, and then for the month in order to provide the open availability for our volunteers to schedule themselves.