So. I had a situation where I needed to do something similar.
Basically the client wanted events that had multiple dates plus they wanted each event date to appear in the archive. To do this I gave them a repeater to set event dates. When they update an event on the acf/save_post hook I create a child post for each event date with all of the needed information from the parent event. The child events are hidden.
This can be done in any number of ways.
The hard part was checking the values submitted against posts that already exist and then creating/deleting post as needed.
