I have a reservation on flight AA104 in J class from JFK to LHR, connecting to a flight within Europe in early December. Initially, my booking only indicated Business class. However, I recently observed that the same flight, albeit terminating in LHR, i.e. with no onward connection is labeled as Flagship Business.

I'm curious about the distinction between the two. Is there a discernible difference in the experience for passengers in Business class versus Flagship Business, even though it's essentially the same flight? The discrepancy is a bit perplexing to me.

Thanks in advance for any clarification.