Hi @Darrin2 I'm not aware of Airbnb ever allowing hosts to determine the amount & timing of payments - it's always been my understanding that Airbnb handles the money, all aspects of the money and as far as I know, this hasn't changed. There are different payment structures depending on the length of the rental, but these are still handled by Airbnb alone.
See this Community Guide for full information:
How Payments Work
There is mention of one way to get around it near the end of the post; perhaps this is what your guest was referring to: "One way around this is asking the host if they would allow you to book half of your dates now and pay and block off the other half so payment can be made later. When ready to pay for the second half, the host would unblock the dates and then you can book and pay for the second half. This would however require a trusting host."
Hope that helps! - Karen