Got this one off the auctions earlier this week. Does not look like any Citizen I have seen before. I assume that the three subdials are independent 12hr counters which are reset with the buttons at 4, 8 and 9. The 10 oclock button should be for the inner bezel. The retrograde day function is a nice technical feature but does not help with the overall design. I do not think there is a chronograph function so your 12hr timing would not be very exact. I can see the need for one or perhaps two 12hr timers but cannot really think of any activity where you would need three of these where your accuracy might be 15 minutes at best. Still an interesting watch though and at 5 bucks per button, I am OK with not being able to use it for anything.
/ martin

/ martin