We often make more than 1000 litres of wort with our 500L model at the shop.
You could stick to one mash and make 1000 litres or do two mashes to get out 2000+ litres. It has a kettle capacity of 1700L so you would make 1500 or 1600 litres of concentrated wort and dilute back to your target gravity to 2000 or more litres. Awesome!
See more info here.