Alertmanager route configurations with `group_by`, `group_interval`, `repeat_interval`, and `group_wait`

Question about alertmanager route configurations. Does anyone know how the settings group_by, group_interval, repeat_interval, and group_wait when they are specified multiple times at routes of different levels throughout the route tree??

Did you ever find anything out about configuring group_by?

https://www.robustperception.io/whats-the-difference-between-group_interval-group_wait-and-repeat_interval

Oh, great. thank you!