Free accounts on Membership are not allowed access to content

I'm moving over to Membership, and have several free accounts that I've assigned free, indefinite subscriptions to. Access rights have been set. But when logging in under a free account, the user is not given access. It appears this is because the user hasn't signed up through a gateway. I see reference in the manual to a "Allow Incomplete Signup" setting in Options, but I see no such setting in the current version of Membership. How do I give an existing user free access?