Theater chain AMC says its new MoviePass-style subscription service, called Stubs A-List, continues to grow at a surprising pace, with more than 500,000 members since its launch back in June. Yet because of that, AMC says it will now have to raise prices in pricier markets like California and New York to offset the higher-than-expected usage rates of subscribers. In some states, the price will increase by $4 to $23.95 a month, while in others it will increase by $2 to $21.95 a month. The pricing changes go into effect on January 9th, 2019.

As a result, AMC says it will offer A-List permanently — it was just offered in a test phase prior to today — and the company will continue to add additional benefits for subscribers. Those benefits include expansions on its reserved seating feature, the ability to order ahead via mobile for food and drink, and the lowering of the minimum required age for members from 18 to 16, with the latter effective immediately and the other two coming by summer of 2019. AMC says more benefits will be announced in the future.

AMC says A-List has more than 500,000 members and will now be offered permanently

“When we launched AMC Stubs A‑List back in June, we did so with the idea that moviegoing could and should be more accessible, convenient, and affordable,” writes CEO Adam Aron in a statement emailed to existing A-List subscribers and standard members of its Stubs rewards program. “Candidly, we are blown away and so appreciative that so many movie fans throughout the United States have agreed. In just four and a half months from the program’s launch, more than 500,000 people will have joined A‑List. Already, after only a few months’ time, one in every 10 guests at an AMC theatre across the country is a member of A‑List and that number seems to grow every day.”

The markets seeing a $4 increase in the monthly price include California, Connecticut, Massachusetts, New Jersey, and New York. all of which feature higher-than-average ticket costs that AMC then has to cover. The markets seeing just a $2 increase are Colorado, Delaware, Florida, Georgia, Illinois, Maryland, Minnesota, Pennsylvania, Virginia and Washington, as well as the District of Columbia.

A-List likely makes most of its money from a mix of subscribers who don’t use it more than twice a month and concessions purchases, the margins for which are extraordinarily high. (A-List also gives you discounts on concessions, incentivizing subscribers to put money that would have otherwise gone to a ticket toward a drink or snack.) But it’s also the case that, like the behavior that eventually forced MoviePass to severely restrict its benefits, a sizable number of subscribers are seeing more than $20 worth of movies every month, causing AMC to lose money on those subscribers. Raising the price just slightly seems to be a reasonable solution by which AMC can continue to offer the program and not lose money on it.

If you’re already a current member, you get to keep your price of $19.95 a month for up to 12 months after your initial sign-up date. And anyone interested in A-List right now can sign up prior to the pricing changes going into effect in January and maintain that discounted price for a full year, AMC says.