G'day,
the JR model doesn´t use the same functionality as the WWTC; it´s more or less a GMT watch (ETA based).
As per GP, there´s the WWTC "Power Reserve" reference 49850.
The case is a bit less wide, with power reserve indication, date, time and (of course) world time.
An interesting watch, particularly those few units without date!
Cheers,
Peter