For our existing students who have purchased the premium plan before 11th Nov 2020 their account is registered primarily with the email id used during onboarding. Thus, all your data, bookmarks, tests, and usage is safe on the cloud even if you Login to a new device with the same credentials (you cannot change your email address once registered).
Note: We have enhanced our Login process recently by allowing students to Log in via an already registered Phone number. Hence, we strongly recommend keeping your phone number intact for a smoother experience. In case of any issue, please Contact us. Our customer care team will get back to you as soon as possible.