Recurring payments paypal IPN

I am working on client's project for paid memberships.

clients want to do recurring payments and i am stumped upon IPN settings for recurring payments.

As Paypal say, if notify_url is specified in html form it will override Paypal's default notify_url if specified. That's fine for one time payment.

But what for recuring payments ? which Settings paypal use for sending IPN notifications to clients server. Is that the notify url which user specified for first time in HTML form or Paypal's default ipn settings ?

what if user hasnot specified paypal default ipn setting ? but had specified it in html form when user was subscribing for the first time.

Any help will be appreciable.

Thanks.

via Chebli Mohamed