@Override
            public SingleSource<? extends byte[]> apply(final BluetoothGattCharacteristic characteristic) throws Exception {
                final SingleSubject<byte[]> subj = SingleSubject.create();
                readCallback.handle(deviceMock, characteristic, new RxBleGattReadResultMock() {
                    @Override
                    public void success(byte[] data) {
                        characteristic.setValue(data);
                        subj.onSuccess(data);
                    }

                    @Override
                    public void failure(int status) {
                        subj.onError(
                                new BleGattCharacteristicException(null,
                                        characteristic,
                                        status,
                                        BleGattOperationType.CHARACTERISTIC_READ)
                        );
                    }

                    @Override
                    public void disconnect(int status) {
                        subj.onError(handleDisconnection(status));
                    }
                });
                return subj;
            }
Value used to disable notifications or indicatinos
mockrxandroidble/src/main/java/com/polidea/rxandroidble2/mockrxandroidble/RxBleConnectionMock.java