The "limited" means you have to have limited intelligence to buy it. Me - I'm buying at least three!!
Why? Its going to be part of the Valhalla collection of 4 whiskies based on 6 gods - see HP website (4 whiskies and 6 gods - what's going on?). There may be 23K in this release but I suspect some of the other Valhalla bottlings may be much released in much more limited numbers if previous experience is anything to go by.
If you manage to get all 4 bottlings as a collection set, I think they will be sought after in future years.