I tried it few weeks back and sadly they force you to add credit card to proceed. Few seconds of googling showed people using fake ones to circumvent it. Not really interested in that nor exposing card details.
I'm on the same boat.
I don't feel comfortable sharing CC details for a free service I might be interested to try (even though I won't have much time until next year to do something), and doesn't seem fair "cheating" the system using a fake one.
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