How can anyone tell yet?
Though Heighway Pinball is going quite fast, I think they're still in design-stage for some of the parts, so who can tell?
I really like what they're doing, I like the layout, the screen on the playfield, the theme, the 'switching playfield-thing' and all the other ideas, but I think they're (or have been) a bit overly optimistic in timeframe, just like JJP was. Producing games before summer would be quite an accomplishment if you ask me!
I'd find it quite an accomplishment if they manage to produce games somewhere this year, but I read they're planning on early summer if I'm not mistaken.
Well, whatever timeframe it'll be: I wish Heighway all the best.