Or they stay on the App Store and none of those fees apply.

From the article:

> iOS apps distributed from the App Store and/or an alternative app marketplace will pay €0.50 for each first annual install per year over a 1 million threshold.

So App Store or not, you need to pay the fee.

>Developers can choose to adopt these new business terms, or stay on Apple’s existing terms. Developers must adopt the new business terms for EU apps to use the new capabilities for alternative distribution or alternative payment processing.

You don’t have to pay the fee if you stay on the existing business terms.

If you are a new business starting after this goes into effect, are you presented with the choice of business terms?

I would assume so.

> Also today, Apple is sharing new business terms available for developers’ apps in the European Union. Developers can choose to adopt these new business terms, or stay on Apple’s existing terms.

Nothing here suggests the new terms replace the existing terms, just that it's now a choice for developers in the EU.

Yes.

ah! Good catch. I missed that the alternative terms were opt-in.