Database Subscriptions - Do Not Disturb mode

Question

Problem:

I am not receiving subscription changes (notifications) to private and shared databases, when the device is in Do Not Disturb Mode (even when the app is in foreground).

Note:

When device is not in Do Not Disturb mode, I receive subscription changes as and when they occur.

Code:

Registering remote notifications:

application.registerForRemoteNotifications()

Database subscriptions:

let subscription = CKDatabaseSubscription(subscriptionID: "Test")
let notificationInfo = CKNotificationInfo()
notificationInfo.shouldSendContentAvailable = true
subscription.notificationInfo = notificationInfo

Receiving Notification:

func application(_ application: UIApplication,
                 didReceiveRemoteNotification userInfo: [AnyHashable : Any],
                 fetchCompletionHandler completionHandler: @escaping (UIBackgroundFetchResult) -> Void) {

    let notification = CKNotification(fromRemoteNotificationDictionary: userInfo)
    
    dataService.receivedCloudKitNotification(notification,
                                             completionBlock: completionHandler)
}

Since I am not using sound / badge / alert / carplay (UNAuthorizationOptions), I had opted for the above method.

My Assumption:

I was assuming that Do Not Disturb would be applicable only for anything that would alert the user visually / or through sound.
I was assuming silent notifications are for data changes and wouldn’t be affected by it. (Just like they don’t require any authorisation)

Questions:

Am I missing any steps for the above mentioned problem ?
On a different scenario, When app is not in Do Not Disturb mode but Background Refresh is turned off for the app I don’t receive subscription changes notifications though the app is in foreground.