@Brian-McG
If we're being precise, we're not talking about the map data that is displayed, but rather about the data used for routing.
I assumed that MRA uses a service (i.e. a REST API) that takes over the routing and thus also accesses a server on which the routing data is stored.
If MRA stores the routing data on its server (yes, as a snapshot), then the developers must also have implemented a routing engine (presumably based on one of the available frameworks).
Regardless of how it is technically implemented, the OSM data is obviously updated in long cycles. However, we should bear in mind that MRA focuses on HERE data, which is why the time lag in OSM data is not so important in my view.