Union Day 2 vs 2 Frigate Event

So this is first event i believe since I started, but am i understanding this right…
You can only use basic Caldari frigates? No other faction ships allowed?

That is correct. You’ll need to be in a fleet of 2 ships, both different Caldari t1 frigates (Any 2 Merlin, Kestrel or Condor).

There’s more restrictions than that - you’ll find them on the filament .