Be afraid...be very afraid.
Looks sweet, and it can be either a IXe or a XVIe for events and ToD.
Nice job HTC.
As for "what is a XVI"?
Its essentially a Spit LF IXe with a Merlin 266 engine. Think improved Spit IX (faster down low, better climb). Clipped wing, E armament (50 cals +20mm), 3 hard points for ord, "broad chord" rudder.
A Spit LF IXe and a Spit XVIe are essentially the same a/c. The XVI has the US built Merlin 66 (Merlin 266).
IXe and XVIe made up a large part of the 44-45 RAF/RCAFs Spitfire force as a med/low alt fighter and fighter-bomber.