Turn on Waitlist when full in Setup, and once every spot is taken the form collects names and emails so you can notify people when a spot opens.
Off by default. With it on, a fully booked form stops taking sign-ups and instead asks for a name and email, so you keep the interest instead of losing it.
Nobody is added automatically and no spot is held, so a freed-up spot is yours to offer to whoever you choose. See how to limit how many people can sign up.
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