KKatP...........
'Base Training' does not involve any revenue flying for the airline concerned.
It usually consists of half a dozen of you all together in the aircraft at a quiet aerodrome somewhere, along with an instuctor qualified to conduct airborne training on the type.
You take it in turns to fly a few visual circuits, with one engine simulated shut down, usually not more than three are required.
What you are getting for your money is the private use of a commercial jet transport with trainer for a couple of hours.
Many pilots consider this to be the last time they ever enjoy flying once they've started the long boring grind of daily commercial life in an airline.
Enjoy!!