I know why there are several reasons for hiring different directors for different episodes. (Eg: some directors are better at action scenes and other at drama) But I wanna know how do they do it?

Meaning, let's take the example of Game of Thrones. There are like 10 subplots that run parallelly throughout the entire season. Then do they simply switch the directors for one scene for that particular episode? What if the shooting is happening in different locations simultaneously? How do they plan? Does the director who is credited to that episode just shoot one of the major scenes while the other scenes are shot by another?