Confused about automatic switching of MasterClient and impact on Players in room

Apologies in advance, I'm sure this is covered in the documentation and other forum threads, however, I have been struggling with it for a while so decided I need to seek help! The below results suggest I am doing something wrong...

Player 1 creates and joins a room.
Player 2 joins the room.
Player 1 (Master Client) disconnects.

At this point I want (and would expect) Player 2 to take over as MasterClient and remain in the room.

However, what I am seeing is Player 2 returns to Master Server when Player 1 disconnects.

Even more confusing to me is the second scenario

Player 1 creates and joins a room.
Player 2 joins the room.
Player 2 leaves the room.

Player 1 (MasterClient) then gets kicked back to Master Server.

my RoomOptions are

var options = new RoomOptions { MaxPlayers = 3, EmptyRoomTtl = 5000, PlayerTtl = 5000, PublishUserId = true, CleanupCacheOnLeave = true, IsOpen = true, IsVisible = true };

Unity 2019.1.5
PUN 2.12