It does.

AFAIK, for IOS, if you want your users to pay via 'web only', you cannot mention anything related to external payment within the app, you cannot have a payment flow within the app.

What you can do is, ask users to sign in and/or visit your web page from where you can convert users. You can run email campaigns etc. Or if your users already have a premium login by making payment elsewhere, that should be fine.