I have a similar problem.
step 1: User clicks on Sign in with Apple button and it displays Apple authorization popup with details like name, share-email, and hide email option then in success response we get an email in received apple identity token.
step 2: Now user revoke signing access from the apple account by following steps (Setting -> Apple account -> Password & Security -> Apple id logins -> remove the app from options)
step 3: After step 2, User clicks again Sign in with the apple button and instead of show the popup at step 1 the user view the usually popup that asks only for code / touch id / face id
I don't think that this is a correct flow, after revoking informations the userId does not change