On some accidentally deleted Firebase, I followed the process per below documentation of Firebase on PITR.

To recover a portion of the database, perform a stale read specifying a query-condition or using direct key lookup along with a timestamp in the past, and then write the results back into the live database

        let organisationRef: FirebaseFirestore.DocumentReference = admin.firestore().collection(ct.parent_coll_).doc("Y2nZURTmgycxTQ8TnJ")
    let readTimestamp = admin.firestore.Timestamp.fromMillis(Date.parse('2024-06-27T16:30:00Z'));

    //retrieve places
    let searchPlaceQuery = parentRef.collection(ct.place_subcoll_)
    .where('api', '==', api).limit(limit);
    if (start_id != null) searchPlaceQuery = searchPlaceQuery.where(admin.firestore.FieldPath.documentId(), ">", start_id)

    const queryPlaceSnapshot = await firestore_root().runTransaction(
        updateFunction => updateFunction.get(searchPlaceQuery),
        { readOnly: true, readTime: readTimestamp }
    );
    console.log("querySnapshot : " + queryPlaceSnapshot.docs.length);

All data was successfully retrieved at some specific time but i have notice for all that the field, type

array

was missing.

Does it need to be looked up with placeRef as if it was a subcollection?

https://firebase.google.com/docs/firestore/pitr