HTC can't answer now. They are too busy making new Beaufighters and Whirlwinds for us.
I'd rather more people fly in the K honestly. Would make for much better turn fights and create more fun furballs because you really have to get in there and actually aim. It's a not a BnZ style plane and it cant dive faster than 500, so it's not necessarily a BnZ, run, easy aim plane like the 190D or P51, which makes a big difference in the fight actually.
On rare occasions I take out some uber planes for a ride just to remember what they are like. Damn the K4 felt totally invincible. Sure, I can escape easier in a P51 or 190D, but with the K4 I could stay in the fight, make nearly every possible mistake and still recover the advantage. Shot all my 60 taters into empty air though and ended up with 3 kills using the cowl guns... 109K4s really do encourage you to play aggressively. All 109s do for that matter.