Question Can you know the id you would get before joining?

Hello,
I am trying to put in the lobby player data the network manager id of the player so I can know which player in the lobby dissconected only from the network manager id. But I have a problem. On network spawn, I want to uptade a list that connects the network manager id with the lobby player index. But I know the id of the player only after spawning so I can't change the lobby player options in time. Do you have any idea what can I do?
Thank you.
(the list is local).