Last year, with the John Mayer limited edition, Audemars Piguet announced the end of its older perpetual calendar movement, the calibre 5134. And indeed, as we have seen with the launch of the next-gen Royal Oak Perpetual Calendar Selfwinding, there is now a new and modern calibre 7138. But it’s not entirely the end of the old JLC-derived movement, as AP had one last trick up its sleeve to celebrate its 150th anniversary: openworked UK perfect replica Audemars Piguet Royal Oak Perpetual Calendar (ref. 26585XT) watches in a mix of titanium and BMG, using the skeletonized calibre 5135. So yes, the 5134 is gone… but it has managed to survive…