The time period does indeed control what ships are available. You won't see the larger ships until the later time periods.
Mainly only in Revolutions and Napoleonic.
Easiest way to find what ships ARE available is to ENABLE_CHEATMODE at the bottom of PROGRAM\InternalSettings.h,
then in Select Storyline click on your ship and start scrolling through all the ones available.
That will show you what ships you might encounter in that particular storyline.
Mainly only in Revolutions and Napoleonic.
Easiest way to find what ships ARE available is to ENABLE_CHEATMODE at the bottom of PROGRAM\InternalSettings.h,
then in Select Storyline click on your ship and start scrolling through all the ones available.
That will show you what ships you might encounter in that particular storyline.
