In Billing › Details › Invoice details, Country is now a list, and there is a Phone field with the flag of the number’s country. A number that cannot be right for that country is marked in red: “That does not look like a mobile or landline number in …”.
A phone number is now required, with the name and country, before a card payment or automatic top-up — sign-up no longer asks for it. In the app, Country is a list you can search. On a phone’s browser, the form is no longer cut off before Country and Save.