Google has chosen to revamp Google Contributor, a service it introduced in 2014 as a way for people to pay to block ads on certain websites.

Google has stopped letting people sign up for the current version of the service. But it is allowing people to ask to be part of a test of the new version, which will be released in early 2017, according to a note on the service’s website.

The service hasn’t received many prominent updates since it first popped up. So it was significant when people who do use Contributor received an email yesterday alerting them to the upcoming changes.

Current Contributor users will see ads again and won’t be able to access their Contributor accounts starting in mid-January 2017, and they won’t be billed from that point forward, according to the email. All remaining money will be refunded. Presumably, those users will have to sign up again to access the new version once it’s available.

It’s interesting that Google isn’t killing Contributor outright; it did have a fair two-year shake. Ultimately, as the biggest moneymaker at Google and its parent company Alphabet, ads are important, and one could imagine that Google is giving Contributor another shot because it would like to see an ad-related product like this become more successful.