Role with Rules

It's not something you want to do at registration-- it's something that needs to happen x days past user creation date.

So, the first thing you have to decide is which event you will use to check for the 'x days' interval. You can setup rules to check at each cron run. Depending on how often you run cron and how many users you have, it could be a large unnecessary overhead for cron to check every user creation date on your site at every cron run.

imo, it's better to check when the user logs in. So you'll need to check the current date against user created + x days.

Then, you need to make a condition for 'if the user does not already have the 'premium' role' (this is a default option if you choose the user login event).

If that condition evaluates to true (does not have the premium role), then add a second condition to check today's date against x days + $account->created (the date_api module has some functions that should be useful here, otherwise see the php date functions). You might be able to do this with the compare numeric values option, if not, you'll have to use the php code option.

Then, for the action, select 'add user role' (also available as an option if you select the user login event) and the premium role you'd like the user to receive.

It's actually not too difficult-- the only tricky part will be to get the date math right. The only thing I don't like about this approach, is that even after the user has been granted the premium role, it will still continue to check the first condition each time the user logs in.

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