Everything was fine. I traveled both ways: from Hai Phong to Sapa and back. The bus schedule was as shown on the app, with a free shuttle service to my hotel in Sapa town. Further distances incur an additional fee. There was no shuttle service on the return trip; I had to go to the pick-up point at 599 Dien Bien Phu myself. The return bus was faster; I arrived back at Vinh Niem bus station by 4 pm.