No, the issue will never go away as long as prior members keep their subscriptions current and new members are stuck with ads or pay a subscription on top of the premium subscription to be ad-less.
I've seen one grandfathered paying member, sure may be few more; honorable that IH show's their appreciation of their founding members.
With the ad model, it will take some time to get everyone on the same plan and I’m not sure what IH has in mind but think the site may become AD revenue generated with min subscription fees which may bring in more users… I would like to see the free members have the same features as premium members. Since free members cannot PM is a value taken away from premium members... IMO