I know it would take a bit more modelling but as there is often 2 Beginners worlds running could one be as it is (2004-2013) and the other say (2010-2019) with some A380 and B787 already on the used market. Also so even beginners can get into some of the prototypes and A320 Neo's and B737 Max's
+1
or a time frame 2015-2024