Board Game Arena

Right, so... as per the subject - what is this setting? What's it do?

It limits the distiller identity pool based on the flight.

In the rule book, there are pairings between Distillers and the Recipe Flights. For Each recipe flight, it gives you 10-12 Distillers who "should" be used with this flight. In most (maybe all) cases, a paired distiller has a "fallback" recipe. For example, If your distiller's signature is "Strong Aroma Baijiu" - Baijiu will also be on the flight or if it is "Cahaina Cachaca", cachaca is on the flight.