Deprecation of Travel Areas: Clarification Required

Summary:

To my understanding, though it's admittedly been a while, Travel Areas are used during the nightly processes that handle the learning of travel time between Travel Keys. The larger the Travel Area you have defined, the slower the learning as there's a cap of x amount of Keys that can be learnt during a run (i want to say 3000). Whereas, multiple Travel Areas allow multiple parallel learning processes to run that focus on the Travel Keys relevant to that Travel Area.

I can see from the documentation that Oracle believe most of their customers do not use this feature correctly or appropriately, but there doesn't appear to be any reference to how this deprecation will affect the learning of travel between keys. Just references to how data will be passed to any routing requests.