Jest create mock of property that reads from the store angular

I'm using Angular, NgRx and Jest.

I'm having the service which is reading from the store

export class MyFacade {
  configuration$ = this.store.select(selectors.selectConfiguration);
}

I'm using it in my spec file in which I'm testing the effects. I have created the mock class that is implementing it like this

export class MyMockFacade {
  configuration$ = of(configObject);
}

and my spec file looks likt this:

describe('Config Effects', () => {
  const mockStore = new MockStore();
    ....
  const mockFacade  = new MyMockFacade();

  let actions;
  let effects: ConfigEffects;

  beforeAll(() => {
    Object.defineProperty(window, 'location', {
      configurable: true,
      value: { reload: jest.fn() }
    });
  });
  beforeEach(() => {
    TestBed.configureTestingModule({
     
      providers: [
        ConfigEffects,
        HttpClientModule,
        provideMockActions(() => actions),
        { provide: Store, useValue: mockStore },
        ...
        { provide: MyFacade , useValue: mockFacade  },
      ]
    });
    effects = TestBed.inject(ConfigEffects);
  });
});

I'd like to have the possibility to change the value returned from the configuration$ in the test. How can I achieve it

 it('should call ....', () => {
    
    //I would like to be able to assigned new value here!

    
      expect(effects.loadXXX$).toSatisfyOnFlush(() => {
        ...
      });
    });

Make configuration$ a BehaviorSubject so you can specify the value it should emit:

export class MyMockFacade {
  configuration$ = new BehaviorSubject<ConfigObject>(null);
}

it('should call ....', () => {
    mockFacade.configuration$.next(someConfigObject); 

    expect(effects.loadXXX$).toSatisfyOnFlush(() => {
      ...
    });
});