I don't really understand what you need to prepare for these forks.
Either a fork will be supported by the ledger or not and if so multiple investors will most likely post here and ask for their forked coins so you dont even need to check it yourself .
Up until ledger doesnt announce any support for a fork you can simply ignore it, right?
The first thing that comes to mind is they would need to take a snapshot of everyone's balances at the time of the fork.