All Gibson F-5s are "Master Models". They have been since 1922. There is also a model called the F-5 Master Model. It's easy to tell, look on the label. F-9, F-5G, Sam Bush, F-5 Fern, Doyle Lawson, etc., #and the F-5 (Master Model).
To have changed the label would have been messing around with history (and I would have angered a whole bunch more folks than confused a very few). There is no more F-5L, F-5V, and I'm working on changing the name on the F-5G. What about going back to the F-12? Haven't made up my mind.