Android BLE Sending more than 20 bytes (without request MTU on client side)

Question

I'm developing an app with BLE features. My server (Peripheral) detect that some clients are connected to my server. I notify them by sending some server's information then after that the client receive those informations he send client's informations.

Server

// Inside BluetoothGattServerCallback I receive the client, add him then try to send data to him
@Override
public void onDescriptorWriteRequest(BluetoothDevice device, int requestId, BluetoothGattDescriptor descriptor, boolean preparedWrite, boolean responseNeeded, int offset, byte[] value) {
super.onDescriptorWriteRequest(device, requestId, descriptor, preparedWrite, responseNeeded, offset, value);

    addDevice(device);
    mHandlerBLE.post(() -> sendInfoServer(device));
}

private void sendInfoServer(BluetoothDevice device) {
    Random r = new Random();
    int nbr = r.nextInt(9999 - 1) + 1;

    JSONObject json = new JSONObject();
    json.put("ID", nbr + "");
    json.put("pic", "totootototototot");
    json.put("cover", "tututututututu");
    json.put("type", "VIP");
    json.put("address", "totoland 4th street");
    json.put("name", "Welcome Toto");

    byte[] data = StringUtils.bytesFromString(json.toString());
    notifyCharacteristic(data, CHARAC_CONNECTION_UUID, device);

    }

private void notifyCharacteristic(byte[] value, UUID uuid, BluetoothDevice device) {
        mHandlerBLE.post(() -> {

            BluetoothGattService service = mGattServer.getService(SERVICE_UUID);
            BluetoothGattCharacteristic characteristic = service.getCharacteristic(uuid);

            characteristic.setValue(value);
            characteristic.addDescriptor(CHARAC_DESCRIPTOR);

            mGattServer.notifyCharacteristicChanged(device, characteristic, false);

        });
    }

My question is : Is it possible to NOTIFY (server to client) more than 20 bytes ? (notifyCharacteristicChanged)

I saw so many code about to split data into chunk and then send it with mBluetoothGatt.writeCharacteristic(characteristic); in a loop.

So I did the same on server side with mGattServer.notifyCharacteristicChanged(device, characteristic, false); but I failed somewhere (so I removed it)

More information (useless maybe) :

Android client to iOS server : OK

iOS client to iOS server : OK

Android client to Android server : OK only if I request MTU on client side but I don't want to.

iOS client to Android server : NOT OK