It kind of makes little sense for a project to be super secretive as you are suggesting and then to have accurate models on display.
These models / pictures have turned out to be misleading in the recent past.. the Turks used to display Ada models for the Pak Navy corvette project, before it was changed to the Jinnah-class design with 16 VLS cells.
PN's Navy News magazine displayed pics of the 1900t Damen OPV which are different from the 2300t ships it is actually getting. The ones built have enough space to install anti-ship/land-attack missile launchers and may get ASW equipment and PDMS/CIWS as well.