Under what circumstances.? Absolute RIP off regardless of how many seats left they were still over 4 grand 3 weeks ago. As you can see from other comments VS are royally taking the P. No matter how many long haul they lay on unopposed in the future, charge these prices and no one will be going. It will hurt business and people will fly on alternatives, cannot see MAN hierarchy being too chuffed when the footfall doesn't appear at Duty Free.
That's how airline booking systems work. I'm not passing judgement on whether it's right or not, but most airlines tend to hike prices if there's only a handful of seats left and particularly the closer it gets to the travel date. Also note it's an A332.