I know the measurements here come direct from the Raffles, but they don’t really make sense. As far as I can tell, Raffles glasses are around 375ml. I made one of these to this recipe in an ice-filled poco grande glass (390ml) and it was full to the absolute brim with no room for soda water. I’d recommend either going for a 20oz hurricane glass or cutting the ingredients by a third, which will allow around 50ml for soda water to top.
Genuinely baffled how the Raffles get round this.