I've noticed that modifying values in the Roku dev portal for products are either delayed or never change. For example, changing the display name of a product doesn't even save in the dashboard. I have successfully changed price tier for a product, but it was definitely not instant. I actually gave up and noticed the following week that the price had finally changed.
It would be awesome if the behavior was documented.
Changing any property of the channel on the developer portal will not take effect until we publish those changes manually. Please email developer at roku.com when you make an update and be sure to tell us what you are changing and we can publish it.
Further, raising the price of your channel will only affect new users, existing users will continue to get the old rate. Lowering the price should lower it for all on the next renewal.