Many of us would appreciate such a service. Actually OBi ATAs have the capability to be configured to automatically update their firmware. However, Obihai hasn't used it lately. They are also slow to update OBi-latest.fw and OBi2-latest.fw, and ***6 doesn't always work, so really it is very difficult to know that a new firmware is released.
At this time, this forum is your best source for firmware updates. When a user discovers one, they post it here.