Just noticed on eBay this AP came in a maximum pimp version...
The article has a 5279 pictured in it with the same waffle pattern on the bezel. Last year I saw the same pattern on the bezel and dial of the manual wind version of that watch. The diamonds are a new twist, maybe aftermarket? Thanks for the photos - now I know the non-date 2120 matches the reference 5279 (mine) and the date 2121 matches reference 5420 (the pictures in your post).
SM300 Watchco on an orange 20mm Planet Ocean OEM strap made from the finest former crocodiles on an OEM Omega 18mm Stainless Steel deployant clasp.
Great thing with a nicely serviced Cal 552, the winding mechanism is so incredibly sensitive that you wear it for an hour or two and it goes for nearly two days. Not a bad thing when the crown is so damn stiff that you can't turn it without rubber gloves.