Kitces points out that Schwab’s model, though better suited for younger people, isn’t for clients without assets—thus the service does not pose a threat to most of the advisors in his XY Planning Network. His network’s clients may not have assets to manage, but they still need financial planning help and are willing to pay for it.

Schwab is not alone in pursuing alternative fee models: Cetera Financial Group recently announced it would support advisors who want to charge planning fees independent of or in lieu of AUM fees, and Merrill Lynch is reportedly considering moving some or all of its digital advice platform to a flat subscription fee.

Though Moore is enthusiastic about all the entries into the space, he argues that there are so many potential clients among mass affluent and high-income, low-asset Americans that the growth of human financial planners employing a subscription fee model will continue unchecked. There are approximately 115 million households in the U.S., which means 55 to 60 million households are earning a median income or above—fertile ground for subscription-based planners.

While both Moore and Kitces believe the AUM model will survive, they also believe subscriptions eventually could eclipse AUM fees. The AUM and commission-based models of financial advice are really targeting the 5% to 7% of American households that can afford the fees and meet the minimums and are willing to delegate responsibility for financial decision making to a professional, says Moore.

And the ability of a subscription-based model to provide advice to underserved—or unserved—markets can help advisors radically expand their client base, as well as serve the clients of their choice at nearly any stage in their adult lives in ways that a more traditional AUM model cannot, says Philip Palaveev, founder and CEO of the Ensemble Practice. “The general public needs financial advice,” says Palaveev. “Unfortunately, we come to some pesky issues. Many people don’t have the resources, the income, the wealth and the money to access financial advice, which is more of a social issue.”

Palaveev also notes that subscription-based services are proliferating in our everyday lives in all the ways we do business. consumers can now pay for office software, clothes, food and toiletries via subscriptions.

And much of middle America is capable of paying for financial advice if the right model is offered to them at a palatable price, says Kitces. “I wrote an article in 2013 arguing that it is not difficult to serve young people with planning; you just have to charge them for it and not make it contingent on selling them a product or charging them on money that they don’t have,” says Kitces. “You have to send them a bill and make them pay for it.”

Essentially, Schwab has merged two different movements bringing financial services to a broader population: robo-advisors and flat-fee planning.

Kitces argues that the growth of human subscription-based financial planners presents a bigger story than Schwab’s success. Six years into the XY Planning Network’s existence, there’s evidence that advisors are enjoying successful careers using a subscription model.

“When starting from scratch, after three years, the average XY Planning Network advisor has $180,000 in annual revenue,” Kitces maintains. “The average LPL advisor does $220,000 of revenue after three years, and those LPL advisors come into their jobs with an average of 10-plus years of experience. So using a subscription model, crossing into year four, an XY Planning Network advisor will have the average revenue of an LPL rep.”