I understand how manual import/export of database works in firestore.

I understand how manual import/export of database works in firestore.

I understand how manual import/export of database works in firestore.

I understand how manual import/export of database works in firestore.

Does an indexed field in a subcollection have it’s own index based on that subcollection (as opposed to the collection as a whole)?

Does an indexed field in a subcollection have it’s own index based on that subcollection (as opposed to the collection as a whole)?

i have data structured in firestore like this

i have data structured in firestore like this

i have data structured in firestore like this

How and when does Google provision Maintenance on the firestore database?
And is there any audit logs for it? Or how notifications can be enabled?