Damn it where's 7th gear when you need it?!
I'd expect the engine was a re-built unit, although cheeky their being cagey about it! If its come from Audi then i'd expect it to of been completely stripped & re-built good as new. More important question to ask is the engine only guaranteed for the balance of the vehicles warranty or 1yr on the engine from date of the replacement. It needs to be treated like a new engine so follow the service book guidelines exactly in terms of 1st oil change cycle.
One other thing, make sure you keep all the receipts & work schedules regarding the engine change really safe, it'll make explaining why there's been an engine change to whoever you sell the car onto a lot easier!
A4 3.0 Quattro Sport - Gone & missed everyday!
Current road going missile.....
........Smart Roadster - arguably the most fun you can have in a car without using lube!!