Era's aren't exactly gonna be shown as a specific event or something, if you were thinking that, whatistitus.
They will simply be 'shown' as progressing technology, access to newer ships, and so on.
A LONG time ago, I proposed having new interfaces every time you 'entered' a new era of development. (So you could have TOS-style screens, then TNG, and so on)
Whilst it would have been awesome eye candy, the idea was rejected because it would simply take too much to program, and would mean that all the interfaces would have to be remade - the devs wouldn't exactly be happy about that, especially since the game is practically complete! 8O
You can still use the Stardate or your level of technology as a guide to the era that you are in though.
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